0383-Ransom-Note.py

'''
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
'''
class Solution:
    def canConstruct(self, ransomNote: str, magazine: str) -> bool:
        a = [0]*26
        for note in magazine:
            a[ord(note) - ord('a')] += 1
        
        for note in ransomNote:
            index = ord(note) - ord('a')
            a[index] -= 1
            if a[index] < 0:
                return False
            
        return True