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") -> false canConstruct("aa", "ab") -> false canConstruct("aa", "aab") -> true都是套路，遇到字符个数，先申请数组，int[] cha=new int[26]
public class Solution { public boolean canConstruct(String ransomNote, String magazine) { int[] cha=new int[26]; for(int i=0;i<magazine.length();i++) { cha[magazine.charAt(i)-'a']+=1; } for(int i=0;i<ransomNote.length();i++) { cha[ransomNote.charAt(i)-'a']-=1; if(cha[ransomNote.charAt(i)-'a']<0) return false; } return true; } }