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feat: add solutions to lc problem: No.0664
No.0664.Strange Printer
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‎solution/0600-0699/0664.Strange Printer/README.md

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<!-- 这里可写通用的实现逻辑 -->
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**方法一：动态规划**
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定义 `dp[i][j]` 表示打印区间 `[i, j]` 所需的最少打印次数。当 `i == j` 时，`dp[i][j] = 1`，即只有一个字符，只需打印一次。答案为 `dp[0][n - 1]`。
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如果 `s[i] == s[j]`，则 `dp[i][j] = dp[i][j - 1]`；否则，`dp[i][j] = min(dp[i][k] + dp[k + 1][j])`，其中 `i <= k < j`。
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时间复杂度 $O(n^3)$，空间复杂度 $O(n^2)$。其中 $n$ 为字符串 `s` 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 strangePrinter(self, s: str) -> int:
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n = len(s)
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dp = [[inf] * n for _ in range(n)]
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for i in range(n - 1, -1, -1):
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dp[i][i] = 1
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for j in range(i + 1, n):
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if s[i] == s[j]:
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dp[i][j] = dp[i][j - 1]
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else:
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for k in range(i, j):
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dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j])
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return dp[0][-1]
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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 int strangePrinter(String s) {
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int n = s.length();
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int[][] f = new int[n + 1][n + 1];
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for (int i = 0; i < n; ++i) {
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f[i][i] = 1;
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}
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for (int i = n - 2; i >= 0; --i) {
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for (int j = i + 1; j < n; ++j) {
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f[i][j] = 1 + f[i + 1][j];
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for (int k = i + 1; k <= j; ++k) {
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if (s.charAt(i) == s.charAt(k)) {
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f[i][j] = Math.min(f[i][j], f[i + 1][k] + f[k + 1][j]);
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}
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}
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}
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}
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return f[0][n - 1];
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}
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}
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```
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```java
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class Solution {
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public int strangePrinter(String s) {
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int n = s.length();
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int[][] dp = new int[n][n];
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for (int i = n - 1; i >= 0; --i) {
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dp[i][i] = 1;
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for (int j = i + 1; j < n; ++j) {
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if (s.charAt(i) == s.charAt(j)) {
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dp[i][j] = dp[i][j - 1];
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} else {
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dp[i][j] = 10000;
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for (int k = i; k < j; ++k) {
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dp[i][j] = Math.min(dp[i][j], dp[i][k] + dp[k + 1][j]);
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}
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}
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}
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}
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return dp[0][n - 1];
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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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int strangePrinter(string s) {
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int n = s.size();
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vector<vector<int>> dp(n, vector<int>(n, INT_MAX));
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for (int i = n - 1; i >= 0; --i) {
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dp[i][i] = 1;
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for (int j = i + 1; j < n; ++j) {
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if (s[i] == s[j]) {
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dp[i][j] = dp[i][j - 1];
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} else {
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for (int k = i; k < j; ++k) {
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dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j]);
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}
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}
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}
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}
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return dp[0][n - 1];
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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 strangePrinter(s string) int {
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n := len(s)
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dp := make([][]int, n)
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for i := range dp {
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dp[i] = make([]int, n)
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}
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for i := n - 1; i >= 0; i-- {
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dp[i][i] = 1
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for j := i + 1; j < n; j++ {
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if s[i] == s[j] {
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dp[i][j] = dp[i][j-1]
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} else {
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dp[i][j] = 10000
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for k := i; k < j; k++ {
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dp[i][j] = min(dp[i][j], dp[i][k]+dp[k+1][j])
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}
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}
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}
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}
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return dp[0][n-1]
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}
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func min(a, b int) int {
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if a < b {
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return a
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}
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return b
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}
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```
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### **...**

‎solution/0600-0699/0664.Strange Printer/README_EN.md

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### **Python3**
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```python
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class Solution:
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def strangePrinter(self, s: str) -> int:
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n = len(s)
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dp = [[inf] * n for _ in range(n)]
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for i in range(n - 1, -1, -1):
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dp[i][i] = 1
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for j in range(i + 1, n):
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if s[i] == s[j]:
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dp[i][j] = dp[i][j - 1]
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else:
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for k in range(i, j):
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dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j])
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return dp[0][-1]
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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 int strangePrinter(String s) {
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int n = s.length();
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int[][] f = new int[n + 1][n + 1];
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for (int i = 0; i < n; ++i) {
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f[i][i] = 1;
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}
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for (int i = n - 2; i >= 0; --i) {
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for (int j = i + 1; j < n; ++j) {
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f[i][j] = 1 + f[i + 1][j];
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for (int k = i + 1; k <= j; ++k) {
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if (s.charAt(i) == s.charAt(k)) {
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f[i][j] = Math.min(f[i][j], f[i + 1][k] + f[k + 1][j]);
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}
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}
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}
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}
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return f[0][n - 1];
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}
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}
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```
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```java
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class Solution {
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public int strangePrinter(String s) {
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int n = s.length();
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int[][] dp = new int[n][n];
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for (int i = n - 1; i >= 0; --i) {
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dp[i][i] = 1;
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for (int j = i + 1; j < n; ++j) {
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if (s.charAt(i) == s.charAt(j)) {
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dp[i][j] = dp[i][j - 1];
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} else {
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dp[i][j] = 10000;
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for (int k = i; k < j; ++k) {
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dp[i][j] = Math.min(dp[i][j], dp[i][k] + dp[k + 1][j]);
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}
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}
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}
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}
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return dp[0][n - 1];
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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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int strangePrinter(string s) {
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int n = s.size();
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vector<vector<int>> dp(n, vector<int>(n, INT_MAX));
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for (int i = n - 1; i >= 0; --i) {
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dp[i][i] = 1;
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for (int j = i + 1; j < n; ++j) {
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if (s[i] == s[j]) {
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dp[i][j] = dp[i][j - 1];
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} else {
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for (int k = i; k < j; ++k) {
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dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j]);
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}
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}
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}
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}
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return dp[0][n - 1];
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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 strangePrinter(s string) int {
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n := len(s)
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dp := make([][]int, n)
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for i := range dp {
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dp[i] = make([]int, n)
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}
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for i := n - 1; i >= 0; i-- {
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dp[i][i] = 1
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for j := i + 1; j < n; j++ {
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if s[i] == s[j] {
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dp[i][j] = dp[i][j-1]
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} else {
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dp[i][j] = 10000
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for k := i; k < j; k++ {
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dp[i][j] = min(dp[i][j], dp[i][k]+dp[k+1][j])
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}
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}
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}
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}
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return dp[0][n-1]
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}
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func min(a, b int) int {
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if a < b {
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return a
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}
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return b
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}
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```
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### **...**

‎solution/0600-0699/0664.Strange Printer/Solution.cpp

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class Solution {
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public:
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int strangePrinter(string s) {
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int n = s.size();
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vector<vector<int>> dp(n, vector<int>(n, INT_MAX));
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for (int i = n - 1; i >= 0; --i) {
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dp[i][i] = 1;
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for (int j = i + 1; j < n; ++j) {
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if (s[i] == s[j]) {
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dp[i][j] = dp[i][j - 1];
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} else {
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for (int k = i; k < j; ++k) {
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dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j]);
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}
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}
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}
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}
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return dp[0][n - 1];
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}
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};

‎solution/0600-0699/0664.Strange Printer/Solution.go

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func strangePrinter(s string) int {
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n := len(s)
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dp := make([][]int, n)
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for i := range dp {
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dp[i] = make([]int, n)
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}
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for i := n - 1; i >= 0; i-- {
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dp[i][i] = 1
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for j := i + 1; j < n; j++ {
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if s[i] == s[j] {
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dp[i][j] = dp[i][j-1]
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} else {
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dp[i][j] = 10000
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for k := i; k < j; k++ {
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dp[i][j] = min(dp[i][j], dp[i][k]+dp[k+1][j])
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}
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}
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}
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}
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return dp[0][n-1]
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}
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func min(a, b int) int {
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if a < b {
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return a
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}
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return b
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}

‎solution/0600-0699/0664.Strange Printer/Solution.java

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class Solution {
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public int strangePrinter(String s) {
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if (s.isEmpty()) {
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return 0;
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}
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int n = s.length();
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int[][] f = new int[n + 1][n + 1];
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for (int i = 0; i < n; ++i) {
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}
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return f[0][n - 1];
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}
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}
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}

‎solution/0600-0699/0664.Strange Printer/Solution.py

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class Solution:
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def strangePrinter(self, s: str) -> int:
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n = len(s)
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dp = [[inf] * n for _ in range(n)]
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for i in range(n - 1, -1, -1):
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dp[i][i] = 1
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for j in range(i + 1, n):
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if s[i] == s[j]:
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dp[i][j] = dp[i][j - 1]
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else:
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for k in range(i, j):
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dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j])
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return dp[0][-1]

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