Compilare: main.cpp: In function 'int main()': main.cpp:58:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 58 | for(i=0;i<vec.size();i++) | ~^~~~~~~~~~~ main.cpp:21:15: warning: unused variable 'k' [-Wunused-variable] 21 | int n,i,j,k,l,m,index,lin,col; | ^ main.cpp:21:17: warning: unused variable 'l' [-Wunused-variable] 21 | int n,i,j,k,l,m,index,lin,col; | ^ main.cpp:21:21: warning: unused variable 'index' [-Wunused-variable] 21 | int n,i,j,k,l,m,index,lin,col; | ^~~~~