Cod sursă (job #585035)

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

using namespace std;
ifstream in("bart.in");
ofstream out("bart.out");

int main()
{
    char v[500001];
    in.get(v, 500001);
    int n = strlen(v);
    int k = 1;
    for(int i = 1; i < n; i ++)
    {
        if(v[i] != v[i-k])
        {
            k = i + 1;
        }
    }
    for(int i = 0; i < k; i ++)
        out << v[i];
    in.close();
    out.close();
    return 0;
}