Compilare: main.cpp: In function 'int main()': main.cpp:70:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 70 | for(int i=0;i<sol.size();i++,fout<<'\n') | ~^~~~~~~~~~~ main.cpp:71:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 71 | for(int j=0;j<sol[i].size();j++) | ~^~~~~~~~~~~~~~