...NULL);printf(“\1: It took you %6.3f seconds\n“,var=(double)(end-start)/18.2);printf(“\1: it took you %6.3f seconds\n\n“,difftime(b,a));if(var〈15)printf(“\1\1 You are very clever! \1\1\n\n“);else if(var〈25)printf(“\1\1 you are normal! \1\1\n\n“);elseprintf(“\1\1 you are stupid! ...