Sum of digits with test cases in C

Question

I am trying to find the sum of digits with test cases. But the problem is after I find one sum, this sum is adding to the next sum but I only one particular sum of that numbers' digit. Please help. Here is my code:


#include <stdio.h>

int main() {
    int t, n, i, r, sum=0;
    scanf("%d", &t);

    for(i=0; i<t; i++) {
        scanf("%d", &n);
        while(n>0) {
            r = n % 10;
            sum = sum + r;
            n = n / 10;
        }
        printf("%d\n", sum);
    }

    return 0;
}

And Here is my output:

Why my previous sum adding to the next sum? I am not understanding.

My desired output:

reset the value of `sum` on every iteration you take new user input — TruthSeeker, Jan 04 '20 at 18:40

Itban Saeed · Accepted Answer · 2020-01-04T18:42:55.723

Problem:

Your variable sum is set to 0 on the start of the program and you are adding the sum of each test case in the same variable without cleaning the result of the previous test case (by setting sum = 0 before the next test case starts.)

Possible Solution:

Initialize your your variable sum before a test case starts.

Code:

for(i=0; i<t; i++)
{
    scanf("%d", &n);

    sum = 0; //Set sum = 0

    //Test Case started in while loop
    while(n>0) {
        r = n % 10;
        sum = sum + r;
        n = n / 10;
    }
    printf("%d\n", sum);
}

score 0 · Answer 2 · answered Jan 04 '20 at 18:34

0

In the begining of your loop set sum to 0. So that before taking sum over next set of elements it is reinitialized to zero.

for(i=0; i<t; i++) 
  { 
    sum = 0;
    scanf("%d", &n);

answered Jan 04 '20 at 18:34

H S

1,211
6
11

score 0 · Answer 3 · answered Jan 04 '20 at 18:35

0

You need to set your sum=0; on the first line of the for loop.

answered Jan 04 '20 at 18:35

Vlad Feinstein

10,960
1
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Sum of digits with test cases in C

3 Answers3