Compilare: main.cpp: In function 'void solve()': main.cpp:63:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 63 | for(int i=0;i<a.size();i++) | ~^~~~~~~~~ main.cpp:83:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 83 | for(int i=0;i<sol.size();i++) | ~^~~~~~~~~~~ main.cpp:98:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 98 | for(int i=0;i<sol.size();i++) | ~^~~~~~~~~~~ main.cpp:95:9: warning: unused variable 'cnt' [-Wunused-variable] 95 | int cnt=0; | ^~~