首页 > 代码库 > [LeetCode]383. Ransom Note 解题小结

[LeetCode]383. Ransom Note 解题小结

题目:

?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.

Note:
You may assume that both strings contain only lowercase letters.

canConstruct("a", "b") -> falsecanConstruct("aa", "ab") -> falsecanConstruct("aa", "aab") -> true

建立字符表,对应字符的个数,如果ransom Note的字符数大于magazine的,返回false。

class Solution {public:    bool canConstruct(string ransomNote, string magazine) {        if(ransomNote.length() > magazine.length()) return false;        int dictRansom[256]={0};        int dictMagazine[256]={0};                for(int i = 0; i < ransomNote.length(); ++i){            dictRansom[ransomNote[i]]++;        }        for(int i = 0; i < magazine.length(); ++i){            dictMagazine[magazine[i]]++;        }                for(int i = 0; i < ransomNote.length(); ++i){            if(dictRansom[ransomNote[i]] > dictMagazine[ransomNote[i]])                return false;        }        return true;    }};

 

[LeetCode]383. Ransom Note 解题小结