LeetCode-in-Java

383. Ransom Note

Easy

Given two stings ransomNote and magazine, return true if ransomNote can be constructed from magazine and false otherwise.

Each letter in magazine can only be used once in ransomNote.

Example 1:

Input: ransomNote = “a”, magazine = “b”

Output: false

Example 2:

Input: ransomNote = “aa”, magazine = “ab”

Output: false

Example 3:

Input: ransomNote = “aa”, magazine = “aab”

Output: true

Constraints:

Solution

public class Solution {
    public boolean canConstruct(String ransomNote, String magazine) {
        int[] a = new int[26];
        int n = ransomNote.length();
        for (int i = 0; i < n; i++) {
            a[ransomNote.charAt(i) - 97]++;
        }
        for (int i = 0; i < magazine.length() && n != 0; i++) {
            if (a[magazine.charAt(i) - 97] > 0) {
                n--;
                a[magazine.charAt(i) - 97]--;
            }
        }
        return n == 0;
    }
}