1050 String Subtraction (20)

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 10^4^. 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<iostream>
#include<string>
using namespace std;
const int maxn = 10010;
bool hashTable[256];
string s1,s2;
int main(){
    getline(cin,s1);
    getline(cin,s2);
    int len1 = s1.length(),len2 = s2.length();
    for(int i = 0 ; i < len2; i++){
        hashTable[s2[i]] = true;
    } 
    for(int i = 0; i < len1 ; i++){
        if(hashTable[s1[i]] == false){
            cout << s1[i];
        }
    }
    return 0;
}