[Data structure template question] DFS (depth first search) enumeration combination number

#include<cstdio>
#include<iostream>
using namespace std;
int n,m,k;

int b[100001];

void print(){
	for(int i=1;i<=m;i++)cout<<b[i]<<' ';
}

void combination(int k){
	if(k==m+1){
		print();
		cout<<endl;
		return;
	}
	
	for(int i=b[k-1]+1;i<=n;i++)
	{
		b[k]=i;
		combination(k+1);
	}
}
int main(){
	cin>>n>>m;
	combination(1);
	
	return 0;
}