시간 제한메모리 제한제출정답맞힌 사람정답 비율
1 초 512 MB47262264.706%

문제

It was a dark and dreary Christmas Eve when our hero pondered, weak and weary, over a quaint and curious COCI task. When he nodded, nearly napping, suddenly he heard a tapping, tapping and a mighty roar. A giant reindeer broke through his chamber door, merely this and nothing more. While our hero’s heart slightly fluttered, the beast simply uttered: “I won’t leave until you solve this problem”.

In the problem you were given two integers N and M and you were supposed to perfectly match the numbers from sets A = {0, 1, 2, . . . , N − 1} and B = {M, . . . , M + N − 1} into N pairs, such that for the matched numbers x ∈ A and y ∈ B it holds x & y = x, where & denotes a bitwise AND operation.

입력

The first line contains two integers N and M (1 ≤ N ≤ M, N + M ≤ 106) from the task description.

출력

You should output N lines and in each line you should output two integers x and y, where x belongs to set A and y belongs to set B. Numbers in each line should correspond to one of the matched pairs from task description.

It is possible to prove that the solution always exists.

서브태스크

번호배점제한
110

N is a power of 2

229

N + M is a power of 2

339

N + M ≤ 1000

432

No additional constraints.

예제 입력 1

1 3

예제 출력 1

0 3

예제 입력 2

3 5

예제 출력 2

0 5
1 7
2 6

예제 입력 3

5 10

예제 출력 3

0 12
1 13
2 10
3 11
4 14

채점 및 기타 정보

  • 예제는 채점하지 않는다.