#include <bits/stdc++.h>   using namespace std;   vector<pair<int, double>> ans[52];   int main() {     int n, w, m;     cin >> n >> w >> m;     double s = (n * w) / (m * 1.0), c = w, b = 1, k = 0;     for (int i = 0; i < m; i++) {       double ne = s;       while (1) {         if (ne + 10e-7 > c) {           ans[i].push_back(make_pair(b, c));           ne -= c;           c = w;           b++;           if (++k > 2) {             cout <<  NO ;             return 0;           }           k = 0;           if (abs(ne) < 10e-7) break;         } else {           ans[i].push_back(make_pair(b, ne));           c -= ne;           k++;           break;         }       }     }     cout <<  YES n ;     for (int i = 0; i < m; i++) {       for (auto it : ans[i])         cout << fixed << setprecision(0) << it.first <<     << setprecision(6)              << it.second <<    ;       cout <<   n ;     }     return 0;   }   