Cod sursă (job #94614)

#include <cstdio>
#include<string.h>
using namespace std;

int main()
{
    FILE *in;
    FILE *out;
    in=fopen("bart.in","r");
    out=fopen("bart.out","w");
    char c[500002];
    fgets(c,500002,in);
    int i,n,k,j,q,citit=1;
    n=strlen(c);
    n=n-2;
    k=1;
    while(k<=n+1 && citit==1)
    {
        q=0;
        for(i=0;i<k;i++)
        {
            for(j=i+k;j<=n;j=j+k)
                if(c[i]!=c[j])
                {
                    q=1;
                    break;
                }
            if(q==1)
                break;
        }

        if(q==0)
        {
            citit=0;
            for(i=0;i<k;i++)
                fprintf(out,"%c",c[i]);
        }
        k++;
    }
    return 0;
}