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Commit 52f6ba4

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Add longest_palindrome
1 parent 02c20ee commit 52f6ba4

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Lines changed: 63 additions & 0 deletions
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// 5. Longest Palindromic Substring, Medium
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// https://leetcode.com/problems/longest-palindromic-substring/
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impl Solution {
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pub fn longest_palindrome(s: String) -> String {
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let n = s.len();
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if n <= 1 {
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return s;
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}
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let chars = s.chars().collect::<Vec<char>>();
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let mut ans = chars[0].to_string();
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let mut dp = vec![vec![false; n]; n];
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for i in 0..n {
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dp[i][i] = true;
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}
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let mut max_len = 0;
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for end in 1..n {
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for start in 0..end {
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if chars[start] == chars[end] {
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if end - start == 1 || dp[start + 1][end - 1] {
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dp[start][end] = true;
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if max_len < end - start + 1 {
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max_len = end - start + 1;
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ans = chars[start..=end].iter().collect::<String>();
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}
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}
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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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struct Solution {}
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#[cfg(test)]
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mod tests {
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use super::*;
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use crate::{vec_string, vec_vec_i32, vec_vec_string};
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#[test]
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fn test_longest_palindrome() {
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assert_eq!(Solution::longest_palindrome("babad".to_string()), "bab".to_string());
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}
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#[test]
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fn test_longest_palindrome2() {
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assert_eq!(Solution::longest_palindrome("cbbd".to_string()), "bb".to_string());
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}
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#[test]
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fn test_longest_palindrome3() {
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assert_eq!(Solution::longest_palindrome("a".to_string()), "a".to_string());
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}
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#[test]
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fn test_longest_palindrome4() {
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assert_eq!(Solution::longest_palindrome("ac".to_string()), "a".to_string());
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}
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}
Lines changed: 2 additions & 1 deletion
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mod group_anagrams;
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mod increasing_triplet;
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mod length_of_longest_substring;
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mod set_zeroes;
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mod longest_palindrome;
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mod set_zeroes;

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