C Exercises: Sum all numbers between two given numbers (inclusive) not divisible by seven

Last update on March 18 2025 13:28:03 (UTC/GMT +8 hours)

Sum numbers between two integers, skipping those divisible by 7

Write a C program to calculate the sum of all numbers between two given numbers (inclusive) not divisible by 7.

Sample Solution:

C Code:

#include <stdio.h>

int main () {
    int a, b, sum_nums = 0, i, temp = 0;

    // Prompt user for input
    printf("Input two numbers(integer):\n");

    // Read two integer values from user and store them in 'a' and 'b'
    scanf("%d %d", &a, &b);

    // Swap 'a' and 'b' if 'b' is smaller than 'a'
    if (b < a) {
        temp = a;
        a = b;
        b = temp;
    }

    // Loop through the range from 'a' to 'b' (inclusive)
    for (i = a; i <= b; i++) {
        // Check if 'i' is not divisible by 7
        if (i % 7 != 0) {
            sum_nums += i; // Accumulate numbers not divisible by 7
        }
    }

    // Print the sum of numbers not divisible by 7
    printf("Sum of all numbers between said numbers (inclusive) not divisible by 7:\n");
    printf("%d\n", sum_nums);

    return 0; // End of program
}

Sample Output:

Input two numbers(integer):
25
5
Sum of all numbers between said numbers (inclusive) not divisible by 7:
273

Sample Output:

Input two numbers(integer):
6
36
Sum of all numbers between said numbers (inclusive) not divisible by 7:
546

Flowchart:

For more Practice: Solve these Related Problems:

Write a C program to compute the sum of all numbers between two integers while skipping numbers divisible by 7 using a loop.
Write a C program to iterate over a range and sum numbers not divisible by 7, using the modulus operator for checks.
Write a C program to compute the sum with a conditional that skips multiples of 7 and prints the final total.
Write a C program to use a function to sum numbers in a range and exclude those divisible by 7, then display the result.

C programming Code Editor:

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