https://www.acmicpc.net/problem/11651
n=int(input())
array = []
for i in range(n):
input_data = input().split()
array.append((int(input_data[0]), int(input_data[1])))
array.sort()
array = sorted(array, key=lambda student: student[1])
for i in array:
print(i[0],i[1])