Compilare: main.cpp: In function 'int main()': main.cpp:5:65: warning: unused variable 'i' [-Wunused-variable] ifstream f("wall.in");ofstream g("wall.out");int main(){int n,k,i,ok=0;f>> n >> k;vector < pair < int, int > > v(n);for (int i = 0; i < n; ++i){f >> v[i].first;v[i].second = i + 1;if(v[i].first < k)ok++;}sort(v.begin (), v.end ());g << ok << "\n";int poz = k;for (int i = n - 1; i >= 0; --i){g << v[i].second << " " << poz << "\n";poz = k - poz + 1;}} ^