You are going to hold a competition of one-to-one game called AtCoder Janken. _(Janken is the Japanese name for Rock-paper-scissors.)_ N players will participate in this competition, and they are given distinct integers from 1 through N. The arena has M playing fields for two players. You need to assign each playing field two distinct integers between 1 and N (inclusive). You cannot assign the same integer to multiple playing fields. The competition consists of N rounds, each of which proceeds as follows:    * For each player, if there is a playing field that is assigned the player's integer, the player goes to that field and fight the other player who comes there.   * Then, each player adds 1 to its integer. If it becomes N+1, change it to 1.  You want to ensure that no player fights the same opponent more than once during the N rounds. Print an assignment of integers to the playing fields satisfying this condition. It can be proved that such an assignment always exists under the constraints given.
N,M = map(int,input().split())
a = 1
b = N
for i in range(M):
    print(a,b)
    a += 1
    b -= 1

N,M = map(int,input().split())

a = 0
b = M+1

for i in range(M//2):
    a += 1
    b -= 1
    print(a,b)

a = M
b = 2*M+2

for i in range((M+1)//2):
    a += 1
    b -= 1
    print(a,b)
