#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;
int REPLACE (char s [100],char x,char y)
{
    int i;
    for (i=0;s[i];i++)
    {
        if (s[i]==x)
        s[i]=y;
    }
    cout<<s;
}
int main ()
{
    char s [100],x,y;
    cin.getline (s,100);
    cin>>x>>y;
    REPLACE(s,x,y);
    return 0;
}