Compilare: user.cpp: In function ‘int main()’: user.cpp:43:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[v[a][0]].size(); ++i) ^ user.cpp:57:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < d.size(); ++i) ^ user.cpp:22:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi, "%hd %hd", &n, &k); ^ user.cpp:26:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi, "%hd %hd", &a, &b); ^