AtCoder Beginner Contest 296

import sys


def solve():
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    n = int(input().rstrip('\n'))
    s = str(input().rstrip('\n'))
    for i in range(1, n):
        if s[i] == s[i-1]:
            print("No")
            exit()
    print("Yes")


if __name__ == '__main__':
    solve()

import sys


def solve():
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    s = [list(str(input().rstrip('\n'))) for _ in range(8)]
    for i in range(8):
        for j in range(8):
            if s[i][j] == "*":
                print(chr(97 + j) + str(8 - i))
                exit()


if __name__ == '__main__':
    solve()

import sys


def solve():
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    n, x = list(map(int, input().rstrip('\n').split()))
    a = sorted(list(map(int, input().rstrip('\n').split())))
    d = {v: 0 for v in a}
    for v in a:
        if v - x in d:
            print("Yes")
            exit()
    print("No")


if __name__ == '__main__':
    solve()