Compilare: user.cpp: In function ‘void do_back(int, long long int, int, int, int)’: user.cpp:36:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (nProd <= vec[maxPos]) ^ user.cpp: In function ‘int main()’: user.cpp:68:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &t); ^ user.cpp:72:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &n, &k); ^ user.cpp:75:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", vec + j); ^