Compilare: user.cpp: In function ‘int main()’: user.cpp:32:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[nc].size();i++){ ~^~~~~~~~~~~~~ user.cpp:15:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d%d",&n,&m,&x); ^ user.cpp:17:34: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&a,&b); ^ user.cpp:22:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&a); ^