Compilare: main.cpp: In function 'std::vector<int> insert_arr(std::vector<int>, std::vector<int>)': main.cpp:20:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i <= a.size(); i++) { ~~^~~~~~~~~~~ main.cpp:21:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j <= b.size(); j++) { ~~^~~~~~~~~~~ main.cpp:48:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i <= a.size(); ++i) ~~^~~~~~~~~~~ main.cpp:49:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j <= b.size(); ++j) ~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:89:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < sol.size(); i++) ~~^~~~~~~~~~~~