ISBN-13 is a new standard for indentifying books. It uses 13 digits d₁d₂d₃d₄d₅d₆d₇d₈d₉d₁₀d₁₁d₁₂d₁₃. The last digit d₁₃ is a checksum, which is calculated from the other digits using the following formula:

If the checksum is 10, replace it with 0. Your program should read the input as a string. Here are sample runs:

10 (di + 3d, + dz + 3d4 + dz + 3d, + d, + 3dz + d, + 3d10 + d1 + 3d12)%10 Enter the first 12 digits of an ISBN-13 as a string: 978013213080 JEnter The ISBN-13 number is 9780132130806 Enter the first 12 digits of an ISBN-13 as a string: 978013213079 JEnter The ISBN-13 number is 9780132130790 Enter the first 12 digits of an ISBN-13 as a string: 97801320 JEnter 97801320 is an invalid input