PAT 1050 String Subtraction

1050 String Subtraction （20 分)

 

Given two strings S​1​​ and S​2​​, S=S​1​​−S​2​​ is defined to be the remaining string after taking all the characters in S​2​​ from S​1​​. Your task is simply to calculate S​1​​−S​2​​ for any given strings. However, it might not be that simple to do it fast.

Input Specification:

Each input file contains one test case. Each case consists of two lines which gives S​1​​ and S​2​​, respectively. The string lengths of both strings are no more than 1. It is guaranteed that all the characters are visible ASCII codes and white space, and a new line character signals the end of a string.

Output Specification:

For each test case, print S​1​​−S​2​​ in one line.

Sample Input:

They are students.
aeiou

Sample Output:

Thy r stdnts.

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define MAXN 10005

map<char,int> mp;
vector<char> vec;


int main(){
    string s1,s2;
    getline(cin,s1);
    getline(cin,s2);

    for(int i=0;i < s2.size();i++){
        mp[s2[i]]++;
    }


    for(int i=0;i < s1.size();i++){
        if(!mp[s1[i]]) cout << s1[i];
    }
    return 0;
}

——