[백준] 15652번 N과 M (4)

import sys 
input=sys.stdin.readline

n,m=map(int,input().split())
s=[]

def dfs(cnt,start):
    if cnt==m:
        print(' '.join(map(str,s)))
        return 

    for i in range(start,n+1):
            s.append(i)
            dfs(cnt+1,i+1)
            s.pop()

dfs(0,1)