#include <cstdio>
#include <stdlib.h>
int main()
{
    int n;
    scanf("%d", &n);
    for(int i = 1 ; i <= n ; i++ )
    {
        char cmd[110];
        sprintf(cmd, "ren _%d.in .%d.in", i,i);
        system(cmd);
        sprintf(cmd, "ren _%d.out .%d.out",i,i);
        system(cmd);
    }
}