#!/usr/bin/python3
n = int(input())

# mapping to [-180, 180)
visited = [False]*720

locations = [int(input().split()[1]) for _ in range(n)]

for i in range(n):
    prev, cur = locations[i], locations[(i+1)%n]
    big, small = max(cur, prev), min(cur, prev)
    if big - small == 180:
        visited = [True]
        break
    if big - small < 180:
        for i in range(small*2 + 360, big*2 + 361):
            visited[i] = True
    else:
        for i in range(0, small*2 + 360 + 1):
            visited[i] = True
        for i in range(big*2 + 360, 720):
            visited[i] = True

if all(visited):
    print("yes")
else:
    i = visited.index(False)
    print("no", i/2 - 180)