int input for in range append list map int input split while len len f

n = int(input())
A = []
B = [0]
for i in range(n):
    A.append(list(map(int, input().split())))
while len(B)!=n:
    m = len(B)
    for i in range(n):
        for j in B:
            if A[j][i]==1:
                B.append(i)
    B = list(set(B))
    if len(B)==m:
        break
if len(B)==n:
    print ("YES")
else:
    print 
    ("NO")