map错误求调

//本人码风怪异，不喜勿喷
#include<bits/stdc++.h>
using namespace std;
map <char,int> m1;
map <char,int> m2;
string s1,s2,s3;
int main(){
	cin >> s1 >> s2 >> s3;
	for(int i = 0;i < s1.size();i++){
		m1[s1[i]]++;
	}
	for(int i = 0;i < s2.size();i++){
		m1[s2[i]]++;
	}
	for(int i = 0;i < s3.size();i++){
		m2[s3[i]]++;
	}
	map<char,int>::iterator it;
	for(it = m2.begin();it != m2.end();it++){
		if(m1[it -> first] != m2[it -> first]){
			cout << "NO" <<endl;
			return 0;
		}
	}
	cout << "YES" << endl;
	return 0;
}