Compilare: main.cpp: In function 'long long int get_ap(const string&, const string&)': main.cpp:12:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < A.size() ; ++i){ ~~^~~~~~~~~~ main.cpp:13:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < B.size() ; ++j){ ~~^~~~~~~~~~ main.cpp:19:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < B.size() ; ++j) dp[A.size()][j + 1] += dp[A.size()][j]; ~~^~~~~~~~~~