README_EN.md

2108. Find First Palindromic String in the Array

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Description

Given an array of strings words, return the first palindromic string in the array. If there is no such string, return an empty string "".

A string is palindromic if it reads the same forward and backward.

 

Example 1:

Input: words = ["abc","car","ada","racecar","cool"]
Output: "ada"
Explanation: The first string that is palindromic is "ada".
Note that "racecar" is also palindromic, but it is not the first.

Example 2:

Input: words = ["notapalindrome","racecar"]
Output: "racecar"
Explanation: The first and only string that is palindromic is "racecar".

Example 3:

Input: words = ["def","ghi"]
Output: ""
Explanation: There are no palindromic strings, so the empty string is returned.

 

Constraints:

• 1 <= words.length <= 100
• 1 <= words[i].length <= 100
• words[i] consists only of lowercase English letters.

Solutions

Python3

class Solution:
    def firstPalindrome(self, words: List[str]) -> str:
        return next((w for w in words if w == w[::-1]), "")

Java

class Solution {
    public String firstPalindrome(String[] words) {
        for (var w : words) {
            boolean ok = true;
            for (int i = 0, j = w.length() - 1; i < j && ok; ++i, --j) {
                if (w.charAt(i) != w.charAt(j)) {
                    ok = false;
                }
            }
            if (ok) {
                return w;
            }
        }
        return "";
    }
}

C++

class Solution {
public:
    string firstPalindrome(vector<string>& words) {
        for (auto& w : words) {
            bool ok = true;
            for (int i = 0, j = w.size() - 1; i < j; ++i, --j) {
                if (w[i] != w[j]) {
                    ok = false;
                }
            }
            if (ok) {
                return w;
            }
        }
        return "";
    }
};

Go

func firstPalindrome(words []string) string {
	for _, w := range words {
		ok := true
		for i, j := 0, len(w)-1; i < j && ok; i, j = i+1, j-1 {
			if w[i] != w[j] {
				ok = false
			}
		}
		if ok {
			return w
		}
	}
	return ""
}

TypeScript

function firstPalindrome(words: string[]): string {
    for (const word of words) {
        let left = 0;
        let right = word.length - 1;
        while (left < right) {
            if (word[left] !== word[right]) {
                break;
            }
            left++;
            right--;
        }
        if (left >= right) {
            return word;
        }
    }
    return '';
}

Rust

impl Solution {
    pub fn first_palindrome(words: Vec<String>) -> String {
        for word in words.iter() {
            let s = word.as_bytes();
            let mut left = 0;
            let mut right = s.len() - 1;
            while (left < right) {
                if (s[left] != s[right]) {
                    break;
                }
                left += 1;
                right -= 1;
            }
            if left >= right {
                return word.clone();
            }
        }
        String::new()
    }
}

C

char* firstPalindrome(char** words, int wordsSize) {
    for (int i = 0; i < wordsSize; i++) {
        int left = 0;
        int right = strlen(words[i]) - 1;
        while (left < right) {
            if (words[i][left] != words[i][right]) {
                break;
            }
            left++;
            right--;
        }
        if (left >= right) {
            return words[i];
        }
    }
    return "";
}

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