A = input()
C = [[0] * 2 for i in range(int(A))]
for x in range(int(A)):
    B = input()
    D = B.split()
    C[x][0] = D[0]
    C[x][1] = D[1]

C.sort()

for x in range(int(A)):
    print(C[x][0] + " " + C[x][1])