Football

足球场上有 $n$ 人，分为 $A,B$ 两队，它们的位置可以用 $0$（$A$ 队）或 $1$（$B$ 队）表示。一般认为，一个队里面凡是有连续 $7$ 个队员站在一起就是危险的。现在给定他们的站位，判断是否危险。 输入仅一行，为一个长度为 $n(1\leqslant n\leqslant100)$ 的 $01$ 串，含义如题意所述。 输出仅一行，如果这种站位危险输出 $\text{YES}$，否则输出 $\text{NO}$。

Petya loves football very much. One day, as he was watching a football match, he was writing the players' current positions on a piece of paper. To simplify the situation he depicted it as a string consisting of zeroes and ones. A zero corresponds to players of one team; a one corresponds to players of another team. If there are at least $ 7 $ players of some team standing one after another, then the situation is considered dangerous. For example, the situation $ 00100110111111101 $ is dangerous and $ 11110111011101 $ is not. You are given the current situation. Determine whether it is dangerous or not.

The first input line contains a non-empty string consisting of characters "0" and "1", which represents players. The length of the string does not exceed $ 100 $ characters. There's at least one player from each team present on the field.

Print "YES" if the situation is dangerous. Otherwise, print "NO".

001001

NO

1000000001

YES