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yanglbmeyanglbme
committedFeb 13, 2023
feat: add solutions to lc problem: No.0555
No.0555.Split Concatenated Strings
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v0.3.0v0.2.0
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‎solution/0500-0599/0555.Split Concatenated Strings/README.md

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Original file line numberDiff line numberDiff line change
@@ -50,22 +50,164 @@
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<!-- 这里可写通用的实现逻辑 -->
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**方法一：贪心**
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我们先遍历字符串数组 `strs`，对于每个字符串 $s$，如果 $s$ 的反转字符串 $t$ 比 $s$ 大，那么我们就将 $s$ 替换为 $t$。
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然后我们再枚举字符串数组 `strs` 的每个位置 $i$ 作为分割点，将字符串数组 `strs` 拆成两部分，分别为 $strs[i + 1:]$ 和 $strs[:i]$，然后将这两部分拼接起来，得到一个新的字符串 $t$。接下来，我们枚举当前字符串 $strs[i]$ 的每个位置 $j$，其后缀部分为 $a=strs[i][j:]$，前缀部分为 $b=strs[i][:j]$，那么我们可以将 $a$、$t$ 和 $b$ 拼接起来，得到一个新的字符串 $cur$，如果 $cur$ 比当前答案大，那么我们就更新答案。这是将 $strs[i]$ 翻转后的情况，我们还需要考虑 $strs[i]$ 不翻转的情况，即将 $a$、$t$ 和 $b$ 的顺序反过来拼接，得到一个新的字符串 $cur$，如果 $cur$ 比当前答案大，那么我们就更新答案。
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最后，我们返回答案即可。
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时间复杂度 $O(n^2)$，空间复杂度 $O(n)$。其中 $n$ 为字符串数组 `strs` 的长度。
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<!-- tabs:start -->
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### **Python3**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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class Solution:
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def splitLoopedString(self, strs: List[str]) -> str:
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strs = [s[::-1] if s[::-1] > s else s for s in strs]
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ans = ''.join(strs)
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for i, s in enumerate(strs):
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t = ''.join(strs[i + 1:]) + ''.join(strs[: i])
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for j in range(len(s)):
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a = s[j:]
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b = s[:j]
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ans = max(ans, a + t + b)
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ans = max(ans, b[::-1] + t + a[::-1])
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return ans
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class Solution {
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public String splitLoopedString(String[] strs) {
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int n = strs.length;
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for (int i = 0; i < n; ++i) {
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String s = strs[i];
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String t = new StringBuilder(s).reverse().toString();
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if (s.compareTo(t) < 0) {
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strs[i] = t;
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}
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}
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String ans = "";
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for (int i = 0; i < n; ++i) {
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String s = strs[i];
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StringBuilder sb = new StringBuilder();
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for (int j = i + 1; j < n; ++j) {
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sb.append(strs[j]);
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}
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for (int j = 0; j < i; ++j) {
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sb.append(strs[j]);
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}
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String t = sb.toString();
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for (int j = 0; j < s.length(); ++j) {
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String a = s.substring(j);
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String b = s.substring(0, j);
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String cur = a + t + b;
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if (ans.compareTo(cur) < 0) {
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ans = cur;
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}
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cur = new StringBuilder(b).reverse().append(t)
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.append(new StringBuilder(a).reverse().toString()).toString();
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if (ans.compareTo(cur) < 0) {
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ans = cur;
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}
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}
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}
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return ans;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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string splitLoopedString(vector<string>& strs) {
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for (auto& s : strs) {
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string t{s.rbegin(), s.rend()};
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s = max(s, t);
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}
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int n = strs.size();
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string ans = "";
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for (int i = 0; i < strs.size(); ++i) {
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auto& s = strs[i];
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string t;
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for (int j = i + 1; j < n; ++j) {
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t += strs[j];
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}
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for (int j = 0; j < i; ++j) {
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t += strs[j];
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}
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for (int j = 0; j < s.size(); ++j) {
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auto a = s.substr(j);
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auto b = s.substr(0, j);
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auto cur = a + t + b;
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if (ans < cur) {
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ans = cur;
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}
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reverse(a.begin(), a.end());
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reverse(b.begin(), b.end());
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cur = b + t + a;
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if (ans < cur) {
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ans = cur;
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}
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}
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}
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return ans;
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}
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};
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```
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### **Go**
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```go
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func splitLoopedString(strs []string) (ans string) {
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for i, s := range strs {
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t := reverse(s)
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if s < t {
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strs[i] = t
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}
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}
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for i, s := range strs {
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sb := &strings.Builder{}
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for _, w := range strs[i+1:] {
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sb.WriteString(w)
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}
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for _, w := range strs[:i] {
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sb.WriteString(w)
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}
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t := sb.String()
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for j := 0; j < len(s); j++ {
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a, b := s[j:], s[0:j]
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cur := a + t + b
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if ans < cur {
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ans = cur
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}
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cur = reverse(b) + t + reverse(a)
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if ans < cur {
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ans = cur
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}
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}
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}
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return ans
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}
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func reverse(s string) string {
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t := []byte(s)
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for i, j := 0, len(t)-1; i < j; i, j = i+1, j-1 {
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t[i], t[j] = t[j], t[i]
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}
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return string(t)
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}
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```
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### **...**

‎solution/0500-0599/0555.Split Concatenated Strings/README_EN.md

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@@ -51,13 +51,145 @@ The answer string came from the fourth looped one, where you could cut from the
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### **Python3**
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```python
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class Solution:
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def splitLoopedString(self, strs: List[str]) -> str:
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strs = [s[::-1] if s[::-1] > s else s for s in strs]
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ans = ''.join(strs)
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for i, s in enumerate(strs):
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t = ''.join(strs[i + 1:]) + ''.join(strs[: i])
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for j in range(len(s)):
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a = s[j:]
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b = s[:j]
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ans = max(ans, a + t + b)
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ans = max(ans, b[::-1] + t + a[::-1])
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return ans
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```
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### **Java**
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```java
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class Solution {
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public String splitLoopedString(String[] strs) {
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int n = strs.length;
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for (int i = 0; i < n; ++i) {
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String s = strs[i];
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String t = new StringBuilder(s).reverse().toString();
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if (s.compareTo(t) < 0) {
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strs[i] = t;
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}
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}
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String ans = "";
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for (int i = 0; i < n; ++i) {
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String s = strs[i];
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StringBuilder sb = new StringBuilder();
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for (int j = i + 1; j < n; ++j) {
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sb.append(strs[j]);
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}
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for (int j = 0; j < i; ++j) {
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sb.append(strs[j]);
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}
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String t = sb.toString();
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for (int j = 0; j < s.length(); ++j) {
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String a = s.substring(j);
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String b = s.substring(0, j);
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String cur = a + t + b;
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if (ans.compareTo(cur) < 0) {
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ans = cur;
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}
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cur = new StringBuilder(b).reverse().append(t)
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.append(new StringBuilder(a).reverse().toString()).toString();
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if (ans.compareTo(cur) < 0) {
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ans = cur;
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}
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}
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}
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return ans;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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string splitLoopedString(vector<string>& strs) {
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for (auto& s : strs) {
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string t{s.rbegin(), s.rend()};
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s = max(s, t);
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}
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int n = strs.size();
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string ans = "";
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for (int i = 0; i < strs.size(); ++i) {
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auto& s = strs[i];
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string t;
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for (int j = i + 1; j < n; ++j) {
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t += strs[j];
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}
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for (int j = 0; j < i; ++j) {
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t += strs[j];
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}
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for (int j = 0; j < s.size(); ++j) {
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auto a = s.substr(j);
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auto b = s.substr(0, j);
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auto cur = a + t + b;
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if (ans < cur) {
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ans = cur;
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}
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reverse(a.begin(), a.end());
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reverse(b.begin(), b.end());
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cur = b + t + a;
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if (ans < cur) {
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ans = cur;
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}
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}
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}
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return ans;
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}
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};
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```
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### **Go**
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```go
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func splitLoopedString(strs []string) (ans string) {
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for i, s := range strs {
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t := reverse(s)
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if s < t {
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strs[i] = t
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}
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}
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for i, s := range strs {
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sb := &strings.Builder{}
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for _, w := range strs[i+1:] {
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sb.WriteString(w)
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}
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for _, w := range strs[:i] {
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sb.WriteString(w)
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}
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t := sb.String()
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for j := 0; j < len(s); j++ {
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a, b := s[j:], s[0:j]
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cur := a + t + b
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if ans < cur {
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ans = cur
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}
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cur = reverse(b) + t + reverse(a)
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if ans < cur {
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ans = cur
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}
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}
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}
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return ans
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}
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func reverse(s string) string {
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t := []byte(s)
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for i, j := 0, len(t)-1; i < j; i, j = i+1, j-1 {
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t[i], t[j] = t[j], t[i]
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}
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return string(t)
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}
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```
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### **...**

‎solution/0500-0599/0555.Split Concatenated Strings/Solution.cpp

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class Solution {
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public:
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string splitLoopedString(vector<string>& strs) {
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for (auto& s : strs) {
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string t{s.rbegin(), s.rend()};
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s = max(s, t);
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}
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int n = strs.size();
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string ans = "";
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for (int i = 0; i < strs.size(); ++i) {
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auto& s = strs[i];
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string t;
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for (int j = i + 1; j < n; ++j) {
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t += strs[j];
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}
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for (int j = 0; j < i; ++j) {
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t += strs[j];
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}
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for (int j = 0; j < s.size(); ++j) {
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auto a = s.substr(j);
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auto b = s.substr(0, j);
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auto cur = a + t + b;
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if (ans < cur) {
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ans = cur;
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}
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reverse(a.begin(), a.end());
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reverse(b.begin(), b.end());
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cur = b + t + a;
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if (ans < cur) {
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ans = cur;
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}
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}
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}
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return ans;
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}
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};

‎solution/0500-0599/0555.Split Concatenated Strings/Solution.go

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func splitLoopedString(strs []string) (ans string) {
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for i, s := range strs {
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t := reverse(s)
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if s < t {
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strs[i] = t
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}
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}
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for i, s := range strs {
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sb := &strings.Builder{}
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for _, w := range strs[i+1:] {
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sb.WriteString(w)
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}
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for _, w := range strs[:i] {
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sb.WriteString(w)
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}
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t := sb.String()
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for j := 0; j < len(s); j++ {
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a, b := s[j:], s[0:j]
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cur := a + t + b
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if ans < cur {
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ans = cur
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}
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cur = reverse(b) + t + reverse(a)
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if ans < cur {
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ans = cur
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}
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}
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}
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return ans
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}
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func reverse(s string) string {
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t := []byte(s)
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for i, j := 0, len(t)-1; i < j; i, j = i+1, j-1 {
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t[i], t[j] = t[j], t[i]
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}
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return string(t)
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}

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