#include <iostream>
#include <string>

using namespace std;

int main()
{
    string s;
    cin >> s;
    if (s.find("0000000") != -1 || s.find("1111111") != -1)
    {
        cout << "YES" << endl;
    }
    else
    {
        cout << "NO" << endl;
    }
    return 0;
}