Compilare: user.cpp: In function ‘int df(int, int)’: user.cpp:31:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:36:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.cpp:39:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&i,&j); ^