03. Ransom_Note.java

class Solution {
    public boolean canConstruct(String ransomNote, String magazine) {
        Map<Character, Integer> map = new HashMap<>();
        for(char ch : magazine.toCharArray()){
            map.put(ch, map.containsKey(ch)?map.get(ch)+1:1 );
        }
        for(char ch : ransomNote.toCharArray()){
            if(!map.containsKey(ch)){
                return false;
            }
            map.put(ch, map.get(ch)-1);
            if(map.get(ch)==0)
                map.remove(ch);
        }
        return true;
    }
}