Compilare: user.cpp: In function ‘std::vector<int> add(std::vector<int>, std::vector<int>)’: user.cpp:16:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] c.push_back((i<a.size() ? a[i]:0)+(i<b.size() ? b[i]:0)+t); ^ user.cpp:16:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] c.push_back((i<a.size() ? a[i]:0)+(i<b.size() ? b[i]:0)+t); ^ user.cpp: In function ‘int main()’: user.cpp:28:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&N); ^