import sys
read=sys.stdin.buffer.read
readline=sys.stdin.buffer.readline
readlines=sys.stdin.buffer.readlines

def det(x1, y1, x2, y2):
    return x1*y2-x2*y1
ps=[tuple(map(int, readline().split())) for i in range(5)]
for p in ps:
    for q in ps:
        if p==q:
            continue
        for r in ps:
            if r==p or r==q:
                continue
            if det(q[0]-p[0], q[1]-p[1], r[0]-p[0], r[1]-p[1])<=0:
                break
        else:
            break
    else:
        print("NO")
        exit()
print("YES")