Compilare: user.cpp: In function ‘int query(int, int)’: user.cpp:50:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<L[a].size();i++) { ^ user.cpp: In function ‘int main()’: user.cpp:65:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&n,&m); ^ user.cpp:67:41: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&v[i].a,&v[i].b); ^ user.cpp:81:55: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int type, x, y; fscanf(f,"%d%d%d",&type,&x,&y); ^