CF96A.Football

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.

佩佳非常热爱足球。一天，当他观看一场足球比赛时，他在一张纸上记录下了球员们当前的位置。为了简化问题，他将这一情况表示为一个仅由 0 和 1 组成的字符串：其中 0 表示某一支球队的球员，1 表示另一支球队的球员。如果某支球队至少有 7 名球员连续站在一起，则该情况被视为“危险”。例如，情况 00100110111111101 是危险的，而 11110111011101 则不是。现给出当前的情况，请判断它是否危险。

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.

第一行输入包含一个非空字符串，由字符 "0" 和 "1" 组成，表示球员。该字符串的长度不超过 100 个字符。场上至少各有一名来自两支队伍的球员。

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

如果情况危险，则输出 “YES”；否则输出 “NO”。