Ransom Note
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
public class Solution {
public boolean canConstruct(String ransomNote, String magazine) {
if (ransomNote == null || ransomNote.length() == 0) {
return true;
}
if (magazine == null || magazine.length() == 0) {
return false;
}
int[] chars = new int[26];
for (int i = 0; i < magazine.length(); i++) {
chars[magazine.charAt(i) - 'a']++;
}
for (int i = 0; i < ransomNote.length(); i++) {
char c = ransomNote.charAt(i);
chars[c - 'a']--;
if (chars[c - 'a'] < 0) {
return false;
}
}
return true;
}
}
Hope this helps,
Michael