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feat: add solutions to lc problem: No.1177
No.1177.Can Make Palindrome from Substring
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‎solution/1100-1199/1177.Can Make Palindrome from Substring/README.md

Lines changed: 99 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -45,22 +45,120 @@ queries[4] : 子串 = "abcda"，可以变成回文的 "abcba
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<!-- 这里可写通用的实现逻辑 -->
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**方法一：前缀和**
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我们可以使用前缀和的思想，预处理出字符串 $s$ 中每个位置的字符出现次数，即 $cnt[i][j]$ 表示字符串 $s$ 中前 $i$ 个字符中第 $j$ 个字母出现的次数。
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对于每个查询 $[left, right, k]$，我们可以利用前缀和计算出 $s[left..right]$ 中每个字母出现的次数，统计出现次数为奇数的字母个数 $x$，则需要替换的次数为 $\frac{x}{2}$，如果 $\frac{x}{2} \leq k$，则可以将 $s[left..right]$ 变成回文串。
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时间复杂度 $O((n + m) \times C)$，空间复杂度 $O(n \times C)$，其中 $n$ 和 $m$ 分别为字符串 $s$ 和查询数组 $queries$ 的长度，而 $C$ 为字符集大小。本题中 $C = 26$。
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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 canMakePaliQueries(self, s: str, queries: List[List[int]]) -> List[bool]:
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n = len(s)
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cnt = [[0] * 26]
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for i, c in enumerate(s, 1):
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j = ord(c) - ord('a')
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t = cnt[-1][:]
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t[j] += 1
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cnt.append(t)
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ans = []
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for left, right, k in queries:
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x = sum((b - a) & 1 for a, b in zip(cnt[right + 1], cnt[left]))
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ans.append(x // 2 <= k)
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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 List<Boolean> canMakePaliQueries(String s, int[][] queries) {
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int n = s.length();
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int[][] cnt = new int[n + 1][26];
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for (int i = 1; i <= n; ++i) {
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int j = s.charAt(i - 1) - 'a';
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for (int k = 0; k < 26; ++k) {
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cnt[i][k] = cnt[i - 1][k];
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}
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cnt[i][j]++;
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}
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List<Boolean> ans = new ArrayList<>();
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for (var q : queries) {
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int left = q[0], right = q[1], k = q[2];
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int x = 0;
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for (int j = 0; j < 26; ++j) {
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x += (cnt[right + 1][j] - cnt[left][j]) & 1;
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}
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ans.add(x / 2 <= k);
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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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vector<bool> canMakePaliQueries(string s, vector<vector<int>>& queries) {
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int n = s.size();
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int cnt[n + 1][26];
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memset(cnt, 0, sizeof cnt);
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for (int i = 1; i <= n; ++i) {
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int j = s[i - 1] - 'a';
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for (int k = 0; k < 26; ++k) {
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cnt[i][k] = cnt[i - 1][k];
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}
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cnt[i][j]++;
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}
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vector<bool> ans;
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for (auto& q : queries) {
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int left = q[0], right = q[1], k = q[2];
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int x = 0;
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for (int j = 0; j < 26; ++j) {
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x += (cnt[right + 1][j] - cnt[left][j]) & 1;
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}
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ans.emplace_back(x / 2 <= k);
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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 canMakePaliQueries(s string, queries [][]int) (ans []bool) {
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n := len(s)
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cnt := make([][26]int, n+1)
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for i := 1; i <= n; i++ {
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j := s[i-1] - 'a'
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for k := 0; k < 26; k++ {
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cnt[i][k] = cnt[i-1][k]
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}
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cnt[i][j]++
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}
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for _, q := range queries {
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left, right, k := q[0], q[1], q[2]
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x := 0
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for j := 0; j < 26; j++ {
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x += (cnt[right+1][j] - cnt[left][j]) & 1
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}
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ans = append(ans, x/2 <= k)
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}
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return
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}
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```
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### **...**

‎solution/1100-1199/1177.Can Make Palindrome from Substring/README_EN.md

Lines changed: 91 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -50,13 +50,103 @@ queries[4]: substring = &quot;abcda&quot;, could be changed to &quot;abcba&quot;
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### **Python3**
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```python
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class Solution:
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def canMakePaliQueries(self, s: str, queries: List[List[int]]) -> List[bool]:
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n = len(s)
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cnt = [[0] * 26]
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for i, c in enumerate(s, 1):
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j = ord(c) - ord('a')
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t = cnt[-1][:]
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t[j] += 1
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cnt.append(t)
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ans = []
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for left, right, k in queries:
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x = sum((b - a) & 1 for a, b in zip(cnt[right + 1], cnt[left]))
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ans.append(x // 2 <= k)
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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 List<Boolean> canMakePaliQueries(String s, int[][] queries) {
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int n = s.length();
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int[][] cnt = new int[n + 1][26];
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for (int i = 1; i <= n; ++i) {
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int j = s.charAt(i - 1) - 'a';
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for (int k = 0; k < 26; ++k) {
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cnt[i][k] = cnt[i - 1][k];
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}
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cnt[i][j]++;
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}
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List<Boolean> ans = new ArrayList<>();
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for (var q : queries) {
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int left = q[0], right = q[1], k = q[2];
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int x = 0;
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for (int j = 0; j < 26; ++j) {
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x += (cnt[right + 1][j] - cnt[left][j]) & 1;
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}
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ans.add(x / 2 <= k);
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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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vector<bool> canMakePaliQueries(string s, vector<vector<int>>& queries) {
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int n = s.size();
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int cnt[n + 1][26];
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memset(cnt, 0, sizeof cnt);
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for (int i = 1; i <= n; ++i) {
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int j = s[i - 1] - 'a';
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for (int k = 0; k < 26; ++k) {
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cnt[i][k] = cnt[i - 1][k];
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}
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cnt[i][j]++;
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}
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vector<bool> ans;
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for (auto& q : queries) {
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int left = q[0], right = q[1], k = q[2];
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int x = 0;
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for (int j = 0; j < 26; ++j) {
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x += (cnt[right + 1][j] - cnt[left][j]) & 1;
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}
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ans.emplace_back(x / 2 <= k);
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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 canMakePaliQueries(s string, queries [][]int) (ans []bool) {
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n := len(s)
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cnt := make([][26]int, n+1)
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for i := 1; i <= n; i++ {
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j := s[i-1] - 'a'
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for k := 0; k < 26; k++ {
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cnt[i][k] = cnt[i-1][k]
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}
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cnt[i][j]++
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}
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for _, q := range queries {
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left, right, k := q[0], q[1], q[2]
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x := 0
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for j := 0; j < 26; j++ {
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x += (cnt[right+1][j] - cnt[left][j]) & 1
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}
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ans = append(ans, x/2 <= k)
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}
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return
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}
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```
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### **...**

‎solution/1100-1199/1177.Can Make Palindrome from Substring/Solution.cpp

Lines changed: 25 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,25 @@
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class Solution {
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public:
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vector<bool> canMakePaliQueries(string s, vector<vector<int>>& queries) {
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int n = s.size();
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int cnt[n + 1][26];
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memset(cnt, 0, sizeof cnt);
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for (int i = 1; i <= n; ++i) {
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int j = s[i - 1] - 'a';
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for (int k = 0; k < 26; ++k) {
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cnt[i][k] = cnt[i - 1][k];
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}
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cnt[i][j]++;
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}
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vector<bool> ans;
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for (auto& q : queries) {
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int left = q[0], right = q[1], k = q[2];
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int x = 0;
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for (int j = 0; j < 26; ++j) {
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x += (cnt[right + 1][j] - cnt[left][j]) & 1;
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}
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ans.emplace_back(x / 2 <= k);
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}
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return ans;
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}
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};

‎solution/1100-1199/1177.Can Make Palindrome from Substring/Solution.go

Lines changed: 20 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,20 @@
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func canMakePaliQueries(s string, queries [][]int) (ans []bool) {
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n := len(s)
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cnt := make([][26]int, n+1)
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for i := 1; i <= n; i++ {
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j := s[i-1] - 'a'
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for k := 0; k < 26; k++ {
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cnt[i][k] = cnt[i-1][k]
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}
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cnt[i][j]++
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}
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for _, q := range queries {
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left, right, k := q[0], q[1], q[2]
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x := 0
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for j := 0; j < 26; j++ {
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x += (cnt[right+1][j] - cnt[left][j]) & 1
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}
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ans = append(ans, x/2 <= k)
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}
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return
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}

‎solution/1100-1199/1177.Can Make Palindrome from Substring/Solution.java

Lines changed: 23 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,23 @@
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class Solution {
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public List<Boolean> canMakePaliQueries(String s, int[][] queries) {
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int n = s.length();
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int[][] cnt = new int[n + 1][26];
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for (int i = 1; i <= n; ++i) {
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int j = s.charAt(i - 1) - 'a';
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for (int k = 0; k < 26; ++k) {
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cnt[i][k] = cnt[i - 1][k];
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}
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cnt[i][j]++;
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}
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List<Boolean> ans = new ArrayList<>();
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for (var q : queries) {
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int left = q[0], right = q[1], k = q[2];
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int x = 0;
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for (int j = 0; j < 26; ++j) {
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x += (cnt[right + 1][j] - cnt[left][j]) & 1;
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}
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ans.add(x / 2 <= k);
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}
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return ans;
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}
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}

‎solution/1100-1199/1177.Can Make Palindrome from Substring/Solution.py

Lines changed: 14 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,14 @@
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class Solution:
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def canMakePaliQueries(self, s: str, queries: List[List[int]]) -> List[bool]:
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n = len(s)
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cnt = [[0] * 26]
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for i, c in enumerate(s, 1):
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j = ord(c) - ord('a')
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t = cnt[-1][:]
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t[j] += 1
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cnt.append(t)
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ans = []
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for left, right, k in queries:
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x = sum((b - a) & 1 for a, b in zip(cnt[right + 1], cnt[left]))
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ans.append(x // 2 <= k)
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return ans

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