Compilare: user.cpp: In function ‘bool comp(std::pair<int, int>, std::pair<int, int>)’: user.cpp:20:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:60:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(si,"%i",&n); ^ user.cpp:64:43: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(si,"%i %i",&v[i].x,&v[i].y); ^