Question

C PROGRAM

A barcode scanner for Universal Product Codes (UPCs) verifies the 12-digit code scanned by comparing the code’s last digit (called a check digit) to its own computation of the check digit from the first 11 digits as follows:

1. Calculate the sum of the digits in the odd-numbered positions (the first, third… eleventh digits) and multiply this sum by 3.

2. Calculate the sum of the digits in the even-numbered positions (the second, fourth… tenth digits) and add this to the previous result.

3. If the last digit of the result from step 2 is 0, then 0 is the check digit. Otherwise, subtract the last digit from 10 to calculate the check digit.

4. If the check digit matches the final digit of the 12-digit UPC, the UPC is assumed correct.

Write a program that prompts the user to enter the 12 digits of a barcode separated by pressing . The program should store the digits in an integer array, calculate the check digit, and compare it to the final barcode digit. If the digits match, output the barcode with the message “validated.” If not, output the barcode with the message “error in barcode.”

Also, output with labels the results from steps 1 and 2 of the check-digit calculations. Note that the “first” digit of the barcode will be stored in element 0 of the array.

Try your program on the following barcodes, three of which are valid. For the first barcode, the result from step 2 is 79 (0 + 9 + 0 + 8 + 4 + 0) * 3 + (7 + 4 + 0 + 0 + 5).

0 7 9 4 0 0 8 0 4 5 0 1

0 2 4 0 0 0 1 6 2 8 6 0

0 1 1 1 1 0 8 5 6 8 0 7

0 5 1 0 0 0 1 3 8 1 0 1

Answer 1

Solution:

#include<stdio.h>

void main()

{

    int oddsum=0,evensum=0;

    int code[15],i,check_digit,last_digit,result;

    printf("Enter the barcode: ");

    for(i=0;i<12;i++)

        scanf("%d",&code[i]);

    

    for(i=0;i<12;i=i+2)

        oddsum=oddsum+code[i];

    

    for(i=1;i<10;i=i+2)

        evensum=evensum+code[i];

    oddsum=oddsum*3;

    result=oddsum+evensum;

    last_digit=result%10;

    if(last_digit!=0)

        check_digit=10-last_digit;

    else

        check_digit=last_digit;

    

    printf("\nSum of digits in odd positions multiplied by 3 is %d",oddsum);

    printf("\nSum of digits in odd positions multiplied by 3 added to Sum of digits in even positions is %d",result);

    

    

    if(check_digit==code[11])

        printf("\nvalidated\n");

    else

        printf("\nerror in barcode\n");

}

Output:

File Edit Selection View Go Debug Terminal Help barcode.c - Programs - Visual Studio Code -ox 2.2 D 0 - EXPLORER e C barcode.c X C> C barcode.c> maino int oddsum=2, evensum=0; int code[15],i, check_digit,last_digit, result; O a go printf("Enter the barcode: "); 8 for(i=0;i<12; i++) scanf("%d",&code[i]); PROBLEMS OUTPUT DEBUG CONSOLE TERMINAL 1: Code + OA X 9 Windows PowerShell Copyright (C) Microsoft Corporation. All rights reserved. Try the new cross-platform PowerShell https://aka.ms/pscore6 V OPEN EDITORS x C barcode.cc V PROGRAMS > .vscode vo C avgcalc.c avgcalc.exe C barcode.c barcode.exe C charscan.c charscan.exe C div.c div.exe C factorial.c factorial.exe C mem.c mem.exe C scalar.c scalar.exe Scores.dat C sorting.c sorting.exe C student_driver.c student_driver.exe student_records.txt student.exe C student.h > C++ > OUTLINE AO PS D:\Programs> cd "d:\Programs\c\"; if ($?) { gcc barcode.c -o barcode }; if ($?) { .barcode } Enter the barcode: 0 7 9 4 0 0 8 0 4 5 0 1 Sum of digits in odd positions multiplied by 3 is 63 Sum of digits in odd positions multiplied by 3 added to Sum of digits in even positions is 79 validated PS D:\Programs\C> cd "d:\Programs\C\"; if ($?) { gcc barcode.c -o barcode }; if ($?) { .\barcode } Enter the barcode: 0 2 4 0 0 1 6 2 8 6 0 Sum of digits in odd positions multiplied by 3 is 39 Sum of digits in odd positions multiplied by 3 added to Sum of digits in even positions is 55 error in barcode PS D:\Programs\C> | in 11. Col5 Spaces: 4 UTF-8 CRLF C Win32 0 1 7:48 AM Type here to search o e .. 95 4) 12/1/2019 O

File Edit Selection View Go Debug Terminal Help barcode.c - Programs - Visual Studio Code -ox 19 D 0 EXPLORER e C barcode.c X C> C barcode.c> maino int oddsum=2, evensum=0; int code[15],i, check_digit,last_digit, result; a go printf("Enter the barcode: "); 8 for(i=0;i<12; i++) scanf("%d",&code[i]); PROBLEMS OUTPUT DEBUG CONSOLE TERMINAL 1: Code + OA X 9 Windows PowerShell Copyright (C) Microsoft Corporation. All rights reserved. Try the new cross-platform PowerShell https://aka.ms/pscore6 V OPEN EDITORS X C barcode.cc V PROGRAMS > .vscode vo C avgcalc.c avgcalc.exe C barcode.c barcode.exe C charscan.c charscan.exe C div.c div.exe C factorial.c factorial.exe C mem.c mem.exe C scalar.c scalar.exe Scores.dat C sorting.c sorting.exe C student_driver.c student_driver.exe student_records.txt student.exe C student.h > C++ > OUTLINE AO PS D:\Programs> cd "d:\Programs\c\"; if ($?) { gcc barcode.c -o barcode }; if ($?) { .\barcode } Enter the barcode: 0 1 1 1 1 0 8 5 6 8 0 7 Sum of digits in odd positions multiplied by 3 is 48 Sum of digits in odd positions multiplied by 3 added to Sum of digits in even positions is 63 validated PS D:\Programs\C> cd "d:\Programs\C\"; if ($?) { gcc barcode.c -o barcode }; if ($?) { .\barcode } Enter the barcode: 0 5 1 0 0 1 3 8 1 0 1 Sum of digits in odd positions multiplied by 3 is 30 Sum of digits in odd positions multiplied by 3 added to Sum of digits in even positions is 39 validated PS D:\Programs\C> in 11. Col5 Spaces: 4 0 UTF-8 ^ 1 Type here to search o CRLF C Win32 7:49 AM . 4) 12/1/2019 e 95

Answer 2

#include<stdio.h>
void main()
{
    int oddsum=0,evensum=0;
    int code[15],i,check_digit,last_digit,result;
    printf("Enter the barcode: ");
    for(i=0;i<12;i++)
        scanf("%d",&code[i]);
    
    for(i=0;i<12;i=i+2)
        oddsum=oddsum+code[i];
    
    for(i=1;i<10;i=i+2)
        evensum=evensum+code[i];
    oddsum=oddsum*3;
    result=oddsum+evensum;
    last_digit=result%10;
    if(last_digit!=0)
        check_digit=10-last_digit;
    else
        check_digit=last_digit;
    
    printf("\nSum of digits in odd positions multiplied by 3 is %d",oddsum);
    printf("\nSum of digits in odd positions multiplied by 3 added to Sum of digits in even positions is %d",result);
    
    
    if(check_digit==code[11])
        printf("\nvalidated\n");
    else
        printf("\nerror in barcode\n");
}