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
Solution：
思路：
Time Complexity: O(magazine.len) Space Complexity: O(1)
Solution Code：
class Solution {
public boolean canConstruct(String ransomNote, String magazine) {
int[] count = new int[26];
for (int i = 0; i < magazine.length(); i++) {
count[magazine.charAt(i) - 'a']++;
}
for (int i = 0; i < ransomNote.length(); i++) {
if(count[ransomNote.charAt(i) - 'a']-- < 1) {
return false;
}
}
return true;
}
}
