The check digit is calculated and added to the numerical code., A human operator types in the numerical code into the computer., The computer calculates the check digit based on the numerical code entered into the computer by a human operator., The computer compares the calculated check digit with the check digit typed in by the human operator., If the two check digits don't match, the human operator has made an error when entering the numerical code., A human operator will be asked by the computer to re-enter the numerical code..

Check digits

由
嵌入

排行榜

視覺風格

選項

切換範本

恢復自動保存: ?