Example: Sum of Numbers in a Given Range in C using Recursion

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// Sum of Numbers in a Given Range in C using Recursion
#include <stdio.h>

// Function to make the sum of given range number
int rec_sum_of_range(int range_start, int range_end, int sum)
{
    sum += range_start;
    range_start++;

    if (range_start < range_end)
        rec_sum_of_range(range_start, range_end, sum);
    else
        return sum + range_start;
}

// It's the main function of the program
int main()
{
    int range_start, range_end, sum = 0;

    // Step-1 Take input from the User
    printf("Start Range: ");
    scanf("%d", &range_start);

    printf("End Range: ");
    scanf("%d", &range_end);

    // Step-3 Call the recursive function rec_sum_of_range() to get the sum of the input range number
    printf("Total Sum: %d", rec_sum_of_range(range_start, range_end, sum));
    return 0;
}