Can someone correct my code, because when i ran it, it doesn't give a correct output

Question

#include <stdio.h>
int main()
{

int sum=0, prod=1, a, b;

printf("Enter a number: \n");

scanf("%d",&a);

while (a!=0)

sum = sum + a%10;
a = a/10;

while (b!=0)

prod = prod + b%10;
b = b/10;

printf("Sum=%d\nProd=%d\n", sum, prod);

return 0;
}

Answer 1

https://code.sololearn.com/cYJts1oisRCZ/?ref=app

Answer 2

It's the modulus operator and its gives remainder
For example
5%2=1

Answer 3

But why do we need it to calculate the sum and the product

Answer 4

It's used to get the least significative digit from "a"

As an example:

a = 345; sum = 0

And

// added curly braces
while (a!=0){
sum = sum + a%10;
a = a/10;
}

345 != 0 => enter loop:

sum = sum + a % 10;

As 345 % 10 = 5 => sum = sum + 5 => sum = 5

Then a = a / 10

a = 345 / 10 => a = 34

Test loop condition:

34 != 0 => enter loop:

sum = sum + a % 10;

34 % 10 = 4 => sum = 5 + 4 => sum = 9

Then a = a / 10

a = 34 / 10 => a = 3

Test loop condition:

3 != 0 => enter loop:

sum = sum + a % 10;

3 % 10 = 3 => sum = 9 + 3 => sum = 12

Then a = a / 10

a = 3 / 10 => a = 0

Test loop condition:Test loop condition:

a == 0 => ends loop...

And sum = 3+4+5 = 12

3 != 0 => enter loop:

Answer 5

I want to know what is the role of the % sign, and the division in the sum and product

Answer 6

b is never initialized. You're most likely operating with some garbage value.

Answer 7

https://code.sololearn.com/cMd42s5MeEXv/?ref=app

Remember to enclose loop body between { }
And assign the value of a to b (b = a;)
Also, you should change + by * in the expression used for "prod"