Given two strings S₁ and S₂, S = S₁ - S₂ is defined to be the remaining string after taking all the characters in S₂ from S₁. Your task is simply to calculate S₁ - S₂ 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 S₁ and S₂, respectively. The string lengths of both strings are no more than 10⁴. 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 S₁ - S₂ in one line.

They are students.
aeiou

Thy r stdnts.

 1 #include<stdio.h>
 2 #include<math.h>
 3 #include<stdlib.h>
 4 #include<string.h>
 5 #include<algorithm>
 6 using namespace std;
 7 
 8 int main()
 9 {
10     char c, s1[10010], s2[10010];
11     int i, len1, len2, hashtable[150] = {};
12     gets(s1);
13     gets(s2);
14     len1 = strlen(s1);
15     len2 = strlen(s2);
16     for(i = 0; i < len2; i++)
17     {
18         c = s2[i];
19         hashtable[c] = 1;
20     }
21     for(i = 0; i < len1; i++)
22     {
23         c = s1[i];
24         if(hashtable[c] == 1)
25             continue;
26         printf("%c", c);
27     }
28     printf("\n");
29     return 0;
30 }