Compilare: user.cpp:27:24: warning: integer overflow in expression [-Woverflow] const int oo = (1<<31)-1; ^ user.cpp: In function ‘int main()’: user.cpp:103:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < v1.size() ; ++ i) ^ user.cpp:105:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0 ; j < v2.size() ; ++ j) ^