#include<bits/stdc++.h>

using namespace std;

void _()
{
    int n, k;
    cin >> n >> k;
    if(k >= n)
    {
        cout << "NO\n";
        return;
    }
    else
    {
         if(k == 1)
         {
             cout << "YES\n";
             cout << n << endl;
             for(int i = 0; i < n; i++)
             {
                cout << i+1 << " " << (i+1)% n  +1<<endl;
             }
             return;
         }
         else 
         {
            int deg = 1;
            vector<int> a(n, 1);
            vector<vector<int>> e(n);
            int ans = 0;
             deg++;
             for(int i = 1; i < n; i++)
             {
                 e[0].push_back(i);
                 ans++;
             }
             if(k == 2)
             {
                 cout << "YES\n"<<n-1 << endl;
                 for(int i = 1; i < n; i++)
                 {
                     cout << 1 << " " << i+1 << endl;
                 }
                 return;
             }
             a[0] = n-1;
             a[1] = 2;
             a[2] = 2;
             e[1].push_back(2);
             ans++;
             deg = 3;
             int ind = 2;
             int i = 1;
             while(deg < k)
             {
                 deg++;
                 i = 1;
                 while(a[ind] < a[ind-1])
                 {
                     a[ind]++;
                     a[ind+i]++;
                     e[ind].push_back(ind+i);
                     ans++;
                     i++;
                 }
             }
             cout << "YES\n" << ans << endl;
             for(int i = 0; i < n; i++)
             {
                 int p = e[i].size();
                 for(int j = 0; j < p; j++)
                 {
                     cout << i+1 << " " << e[i][j]+1 << endl;
                 }
             }
         }
         
    }
    
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    int t = 1;
    //cin >> t;
    while(t--) _();
}