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feat: add solutions to lc problem: No.0990.Satisfiability of Equality Equations
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‎solution/0900-0999/0990.Satisfiability of Equality Equations/README.md

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<li><code>equations[i][2]</code>&nbsp;是&nbsp;<code>&#39;=&#39;</code></li>
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</ol>
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## 解法
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<!-- 这里可写通用的实现逻辑 -->
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并查集。
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模板 1——朴素并查集：
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```python
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# 初始化，p存储每个点的祖宗节点
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p = [i for i in range(n)]
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# 返回x的祖宗节点
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def find(x):
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if p[x] != x:
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# 路径压缩
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p[x] = find(p[x])
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return p[x]
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# 合并a和b所在的两个集合
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p[find(a)] = find(b)
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```
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模板 2——维护 size 的并查集：
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```python
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# 初始化，p存储每个点的祖宗节点，size只有当节点是祖宗节点时才有意义，表示祖宗节点所在集合中，点的数量
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p = [i for i in range(n)]
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size = [1] * n
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# 返回x的祖宗节点
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def find(x):
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if p[x] != x:
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# 路径压缩
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p[x] = find(p[x])
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return p[x]
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# 合并a和b所在的两个集合
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size[find(b)] += size[find(a)]
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p[find(a)] = find(b)
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```
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模板 3——维护到祖宗节点距离的并查集：
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```python
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# 初始化，p存储每个点的祖宗节点，d[x]存储x到p[x]的距离
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p = [i for i in range(n)]
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d = [0] * n
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# 返回x的祖宗节点
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def find(x):
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if p[x] != x:
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t = find(p[x])
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d[x] += d[p[x]]
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p[x] = t
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return p[x]
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# 合并a和b所在的两个集合
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p[find(a)] = find(b)
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d[find(a)] = dinstance
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```
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对于本题，先遍历所有的等式，构造并查集。接着遍历所有不等式，如果不等式的两个变量处于同一个集合，说明发生矛盾，返回 false。否则遍历结束返回 true。
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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 equationsPossible(self, equations: List[str]) -> bool:
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p = [i for i in range(26)]
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def find(x):
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if p[x] != x:
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p[x] = find(p[x])
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return p[x]
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for e in equations:
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a, r, b = ord(e[0]) - ord('a'), e[1:3], ord(e[3]) - ord('a')
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if r == '==':
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p[find(a)] = find(b)
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for e in equations:
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a, r, b = ord(e[0]) - ord('a'), e[1:3], ord(e[3]) - ord('a')
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if r == '!=' and find(a) == find(b):
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return False
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return True
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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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private int[] p;
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public boolean equationsPossible(String[] equations) {
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p = new int[26];
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for (int i = 0; i < 26; ++i) {
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p[i] = i;
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}
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for (String e : equations) {
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int a = e.charAt(0) - 'a', b = e.charAt(3) - 'a';
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String r = e.substring(1, 3);
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if ("==".equals(r)) {
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p[find(a)] = find(b);
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}
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}
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for (String e : equations) {
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int a = e.charAt(0) - 'a', b = e.charAt(3) - 'a';
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String r = e.substring(1, 3);
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if ("!=".equals(r) && find(a) == find(b)) {
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return false;
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}
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}
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return true;
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}
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private int find(int x) {
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if (p[x] != x) {
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p[x] = find(p[x]);
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}
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return p[x];
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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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vector<int> p;
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bool equationsPossible(vector<string>& equations) {
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p.resize(26);
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for (int i = 0; i < 26; ++i)
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p[i] = i;
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for (auto e : equations)
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{
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int a = e[0] - 'a', b = e[3] - 'a';
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char r = e[1];
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if (r == '=')
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p[find(a)] = find(b);
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}
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for (auto e : equations)
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{
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int a = e[0] - 'a', b = e[3] - 'a';
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char r = e[1];
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if (r == '!' && find(a) == find(b))
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return false;
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}
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return true;
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}
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int find(int x) {
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if (p[x] != x)
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p[x] = find(p[x]);
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return p[x];
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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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var p []int
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func equationsPossible(equations []string) bool {
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p = make([]int, 26)
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for i := 1; i < 26; i++ {
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p[i] = i
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}
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for _, e := range equations {
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a, b := int(e[0]-'a'), int(e[3]-'a')
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r := e[1]
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if r == '=' {
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p[find(a)] = find(b)
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}
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}
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for _, e := range equations {
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a, b := int(e[0]-'a'), int(e[3]-'a')
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r := e[1]
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if r == '!' && find(a) == find(b) {
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return false
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}
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}
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return true
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}
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func find(x int) int {
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if p[x] != x {
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p[x] = find(p[x])
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}
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return p[x]
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}
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```
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### **...**

‎solution/0900-0999/0990.Satisfiability of Equality Equations/README_EN.md

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@@ -141,13 +141,132 @@
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### **Python3**
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```python
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class Solution:
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def equationsPossible(self, equations: List[str]) -> bool:
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p = [i for i in range(26)]
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def find(x):
149+
if p[x] != x:
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p[x] = find(p[x])
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return p[x]
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for e in equations:
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a, r, b = ord(e[0]) - ord('a'), e[1:3], ord(e[3]) - ord('a')
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if r == '==':
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p[find(a)] = find(b)
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for e in equations:
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a, r, b = ord(e[0]) - ord('a'), e[1:3], ord(e[3]) - ord('a')
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if r == '!=' and find(a) == find(b):
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return False
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return True
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```
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### **Java**
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```java
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class Solution {
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private int[] p;
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public boolean equationsPossible(String[] equations) {
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p = new int[26];
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for (int i = 0; i < 26; ++i) {
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p[i] = i;
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}
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for (String e : equations) {
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int a = e.charAt(0) - 'a', b = e.charAt(3) - 'a';
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String r = e.substring(1, 3);
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if ("==".equals(r)) {
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p[find(a)] = find(b);
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}
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}
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for (String e : equations) {
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int a = e.charAt(0) - 'a', b = e.charAt(3) - 'a';
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String r = e.substring(1, 3);
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if ("!=".equals(r) && find(a) == find(b)) {
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return false;
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}
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}
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return true;
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}
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private int find(int x) {
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if (p[x] != x) {
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p[x] = find(p[x]);
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}
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return p[x];
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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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vector<int> p;
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bool equationsPossible(vector<string>& equations) {
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p.resize(26);
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for (int i = 0; i < 26; ++i)
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p[i] = i;
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for (auto e : equations)
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{
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int a = e[0] - 'a', b = e[3] - 'a';
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char r = e[1];
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if (r == '=')
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p[find(a)] = find(b);
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}
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for (auto e : equations)
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{
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int a = e[0] - 'a', b = e[3] - 'a';
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char r = e[1];
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if (r == '!' && find(a) == find(b))
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return false;
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}
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return true;
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}
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int find(int x) {
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if (p[x] != x)
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p[x] = find(p[x]);
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return p[x];
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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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var p []int
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func equationsPossible(equations []string) bool {
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p = make([]int, 26)
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for i := 1; i < 26; i++ {
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p[i] = i
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}
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for _, e := range equations {
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a, b := int(e[0]-'a'), int(e[3]-'a')
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r := e[1]
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if r == '=' {
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p[find(a)] = find(b)
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}
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}
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for _, e := range equations {
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a, b := int(e[0]-'a'), int(e[3]-'a')
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r := e[1]
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if r == '!' && find(a) == find(b) {
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return false
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}
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}
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return true
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}
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func find(x int) int {
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if p[x] != x {
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p[x] = find(p[x])
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}
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return p[x]
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}
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```
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### **...**

‎solution/0900-0999/0990.Satisfiability of Equality Equations/Solution.cpp

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class Solution {
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public:
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vector<int> p;
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bool equationsPossible(vector<string>& equations) {
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p.resize(26);
7+
for (int i = 0; i < 26; ++i)
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p[i] = i;
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for (auto e : equations)
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{
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int a = e[0] - 'a', b = e[3] - 'a';
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char r = e[1];
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if (r == '=')
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p[find(a)] = find(b);
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}
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for (auto e : equations)
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{
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int a = e[0] - 'a', b = e[3] - 'a';
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char r = e[1];
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if (r == '!' && find(a) == find(b))
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return false;
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}
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return true;
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}
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int find(int x) {
27+
if (p[x] != x)
28+
p[x] = find(p[x]);
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return p[x];
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}
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};

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