#include<bits/stdc++.h>
using namespace std;

void solve(){
    int n,k;
    cin>>n>>k;
    
    if(n==k){
        if(n==1){
            cout<<"YES\n";
            cout<<"0\n";
        }
        else cout<<"NO\n";
    }else{
        vector<int> tmp;
        for(int i=1;i<=n;i++)tmp.push_back(i);
        int old = n, oldk=k;
        vector<pair<int,int>> ans;
        while(k>2){
            for(int i=0;i+1<(int)tmp.size();i++){
                ans.push_back({tmp[i],tmp.back()});
            }
            
            tmp.pop_back();
            tmp.pop_back();
            n-=2;
            k-=2;
        }
        
        if(k==1){
            for(int i=0;i<(int)tmp.size();i++){
                for(int j=0;j<i;j++){
                    ans.push_back({tmp[i],tmp[j]});
                }
            }
        }else{
            for(int i=0;i+1<(int)tmp.size();i++){
                ans.push_back({tmp[i],tmp[i+1]});
            }
        }
        
        cout<<"YES\n";
        cout<<ans.size()<<"\n";
        for(auto [u,v] : ans)cout<<u<<" "<<v<<"\n";
    }
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    
    int t=1;
    //cin>>t;
    solve();
    
    return 0;
}