Compilare: main.cpp: In function 'int main()': main.cpp:18:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | for(int i = 0; i < a.size() - 1; i++) | ~~~^~~~~~~~~~~~~~ main.cpp:25:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 25 | for(int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~