Compilare: user.cpp: In function ‘int main()’: user.cpp:32:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(prs.size() != n - 1) ^ user.cpp:25:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d " ,&n,&m); ^ user.cpp:27:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d " ,&x,&y); ^