python

n=int(input())
my_range=range(1,n*n+1)
matrix=[[None for i in range(n)] for i in range(n)]
for i in range(0,n):
    j=i+1
    matrix[i]=[i for i in range(j*n-(n-1),j*n+1)]
for i in range(1,n+1):
    if i%2==0:
        matrix[i-1]=matrix[i-1][::-1]
for i in matrix:
    print(*i)