[leetcode]383. Ransom Note

[leetcode]383. Ransom Note

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Analysis

雨很大~—— [ummm~]

Given an arbitrary ransom note string and another string containing letters from all the magazines, write a function that will return true if the ransom note can be constructed from the magazines ; otherwise, it will return false.
Each letter in the magazine string can only be used once in your ransom note.

给两个字符串，判断第一个字符串是否能由第二个字符串中的字符组成，注意第二个字符串中的每个字符只能用一次。

Implement

class Solution {
public:
    bool canConstruct(string ransomNote, string magazine) {
        int lenM = magazine.length();
        int lenR = ransomNote.length();
        vector<int> has(26, 0);
        for(int i=0; i<lenM; i++)
            has[magazine[i]-'a']++;
        for(int i=0; i<lenR; i++){
            if(has[ransomNote[i]-'a'] == 0)
                return false;
            has[ransomNote[i]-'a']--;
        }
        return true;
    }
};