Compilare: main.cpp: In function 'std::vector<int> solve(const std::vector<std::vector<int> >&)': main.cpp:16:31: warning: variable 'p' set but not used [-Wunused-but-set-variable] 16 | pair<int,int> p = v[i]; | ^ main.cpp:17:22: warning: unused variable 'ok' [-Wunused-variable] 17 | bool ok = true; | ^~ main.cpp: In function 'int main()': main.cpp:55:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 55 | for(int i = 0;i < ret.size();++i) | ~~^~~~~~~~~~~~