I am trying to derive a validation code in which the program would produce a computational answer when executed. For this question the numbers are...

I am trying to derive a validation code in which the program would produce a computational answer when executed.For this question the numbers are assumed to be 4 digit numbers. The program may assume it has received a valid 4 digit number. The validation is based on adding the first digit, two times the second digit, and the third digit and considering the last digit of this computation.