// 从第一个字符串中删除第二个字符串中出现过的所有字符

#include <stdio.h>

char* remove_second_from_first( char *first, char *second )

{

    if( first == NULL || second == NULL )

    {

        printf("first or/and second should not be NULL\n");

        return NULL;

    }

    char flag[]={};

    char *p, *q;

    p = second;

    while( *p != '\0' )

        flag[*p++] = ;

    p = q = first;

    while( *q != '\0' )

    {

        if( flag[*q] ==  )

        {

            q++;

            continue;

        }

        *p++ = *q++;

    }

    *p = '\0';

    return first;

}

int main(void)

{

    char s1[], s2[];

    scanf("%s",s1);

    scanf("%s",s2);

    char *result = remove_second_from_first(s1,s2);

    printf("%s\n",result);

    return ;

}