IMP pb1 10/16/2019

#include <iostream>
#include <cstring>
#include <stdio.h>
using namespace std;

int main()
{
    char s[256], c1[22], c2[22], *p, aux[22];
    gets(s);
    cin >> c1 >> c2;
    int n1 = strlen(c1);
    p = strstr(s, c1);
    while (p)
    {
        strcpy(aux, c2);
        strcat(aux, p + n1);
        strcpy(p, aux);
        p = strstr(s + 1, c1);
    }

    puts(s);
    return 0;
}