# Common Permutation

Common Permutation

Given two strings a and b, print the longest string x of letters such that there is a permutation of x that is a subsequence of a and there is a permutation of x that is a subsequence of b.

The input file contains several cases, each case consisting of two consecutive lines. This means that lines 1 and 2 are a test case, lines 3 and 4 are another test case, and so on. Each line contains one string of lowercase characters, with first line of a pair denoting a and the second denoting b. Each string consists of at most 1,000 characters.

For each set of input, output a line containing x. If several x satisfy the criteria above, choose the first one in alphabetical order

``````pretty
women
walking
down
the
street``````

``````e
nw
et``````

``````#include<stdio.h>
#include<string.h>
int main()
{
int k,j;
char a,b,i;
do
{
gets(a);
gets(b);
for(i='a';i<='z';i++)
{
for(j=0;j<strlen(a);j++)
{
if(a[j]==i)
{
for(k=0;k<strlen(b);k++)
{
if(b[k]==a[j])
{
printf("%c",i);
break;
}
}
break;
}
}
}
printf("\n");
}while(scanf("%d",&a)!=EOF);
return 0;
}``````

``````#include<iostream>
#include<stdio.h>
#include<string.h>
using namespace std;
int a;
int main()
{
char c,d;
while(gets(c))
{
gets(d);
memset(a,0,sizeof(a));
for(int i=0; i<strlen(c); i++)
for(int j=0; j<strlen(d); j++)
if(c[i]==d[j])a[c[i]]++;
for(int i=65; i<130; i++)
if(a[i])printf("%c",i);
printf("\n");
}
return 0;
}
``````