a.cpp

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pii;
template <typename T1, typename T2>
ostream &operator <<(ostream &os, pair<T1, T2> p){os << p.first << " " << p.second; return os;}
template <typename T>
ostream &operator <<(ostream &os, vector<T> &v){for(T i : v)os << i << ", "; return os;}
template <typename T>
ostream &operator <<(ostream &os, set<T> s){for(T i : s) os << i << ", "; return os;}
template <typename T1, typename T2>
ostream &operator <<(ostream &os, map<T1, T2> m){for(pair<T1, T2> i : m) os << i << endl; return os;}

int main(){
    string s;
    cin >> s;
    char curr = '0';
    int currl = 0;
    for(int i = 0; i < (int)s.length(); i++){
        if(curr == s[i]) currl++;
        else currl = 1;
        curr = s[i];
        if(currl >= 7){
            cout << "YES" << endl;
            return 0;   
        }
    }
    cout << "NO" << endl;
    return 0;
}