Compilare: main.cpp: In function 'void solve1()': main.cpp:30:17: warning: unused variable 'cnt' [-Wunused-variable] int cnt = 0; ^~~ main.cpp: In function 'void solve2()': main.cpp:55:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i <= it.second.first.size(); i++) ~~^~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:69:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < s.size(); j++) ~~^~~~~~~~~~