Print all combinations which can be made by $k$ different elements from $0, 1, ..., n-1$. Note that we represent $0, 1, ... n-1$ as 00...0001, 00...0010, 00...0100, ..., 10...0000 in binary respectively and the integer representation of a combination is calculated by bitwise OR of the selected elements.

Constraints

* $1 \leq n \leq 18$
* $k \leq n$

Input

The input is given in the following format.


$n \; k$


Output

Print the combinations ordered by their decimal integers. Print a combination in the following format.


$d$: $e_0$ $e_1$ ...


Print ':' after the integer value $d$, then print elements $e_i$ in the combination in ascending order. Separate two adjacency elements by a space character.

Example

Input

5 3


Output

7: 0 1 2
11: 0 1 3
13: 0 2 3
14: 1 2 3
19: 0 1 4
21: 0 2 4
22: 1 2 4
25: 0 3 4
26: 1 3 4
28: 2 3 4
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
#define max0(a,b,c) max(max(a,b),c)
#define min0(a,b,c) min(min(a,b),c)
#define ft first
#define sc second
#define pb push_back
#define all(v) (v).begin(),(v).end()
#define mod 1000000007
using namespace std;
using Graph = vector<vector<int>>;
typedef long long lint;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ldouble;
typedef vector<int> vec;
typedef vector<ll> lvec;
typedef vector<ull> ulvec;
typedef vector<double> dvec;
typedef vector<pair<int,int>> pvec;
typedef vector<pair<ll,ll>> plvec;
typedef vector<tuple<ll,ll,ll>> tvec;
typedef vector<string> svec;

int main(){
    int n,k;
    cin>>n>>k;
    for(int i=0;i<(1<<n);i++){
        set<int> st;
        for(int j=0;j<n;j++){
            if(i>>j&1) st.insert(j);
        }
        if(st.size()==k){
            cout<<i<<':';
            while(!st.empty()){
                int m=*begin(st);
                st.erase(m);
                cout<<' '<<m;
            }
            cout<<endl;
        }
    }
}
