Compilare: user.cpp: In function ‘std::vector<int> add(std::vector<int>, std::vector<int>)’: user.cpp:15:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i < a.size()) ^ user.cpp:17:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i < b.size()) ^ user.cpp: In function ‘int main()’: user.cpp:27:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, n, k, d1, d2; ^ user.cpp:30:45: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d %d %d " ,&n,&k,&d1,&d2); ^