int input list map int input split for in range for in range for in ra

n = int(input())
w = [list(map(int, input().split())) for i in range(n)]

for k in range(n): 
    for i in range(n):
        for j in range(n):
            if w[i][j] > w[i][k] + w[k][j]:
                w[i][j] = w[i][k] + w[k][j]

print(max([max(p) for p in w])