Ransom note

ransom.cpp

#include <iostream>
#include <string>
#include <map>
using namespace std;

bool ransom( string note, string mag ){
    if( mag.empty() ) return false;
    if( note.empty()) return true;
    int length = note.length();
    int length_mag = mag.length();
    if( length > length_mag ) return false;
    
    map<char, int> note_m;
    for( int i = 0; i < length; ++i){
        note_m[note[i]]++;
    }

    for( int i = 0; i < length_mag; ++i){
        if( note_m[mag[i]] > 0 ){
            note_m[mag[i]]--;
            length--;
        }
        if( length <= 0 ) return true;
    }

    if( length <= 0 ) return true;
    else 
        return false;
}


void main(){
    string s = "hello";
    string mag = "dsfhsfhjskfhelerereo";
    if( ransom(s, mag) ) cout << "YES" <<endl;
    else
        cout << "NOP" << endl;

    cin.get();
}