Variadic functions in C Hackerrank solution

Variadic functions are functions which take a variable number of arguments. In C programming, a variadic function will contribute to the flexibility of the program that you are developing.

The declaration of a variadic function starts with the declaration of at least one named variable, and uses an ellipsis as the last parameter, e.g.

int printf(const char* format, ...);

In this problem, you will implement three variadic functions named ,  and  to calculate sums, minima, maxima of a variable number of arguments. The first argument passed to the variadic function is the count of the number of arguments, which is followed by the arguments themselves.

Input Format

• The first line of the input consists of an integer .
• Each test case tests the logic of your code by sending a test implementation of 3, 5 and 10 elements respectively.
• You can test your code against sample/custom input.
• The error log prints the parameters which are passed to the test implementation. It also prints the sum, minimum element and maximum element corresponding to your code.

Constraints

Output Format

"Correct Answer" is printed corresponding to each correct execution of a test implementation."Wrong Answer" is printed otherwise.

Sample Input 0

1
Sample Output 0

Correct Answer
Correct Answer
Correct Answer

Solution

#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define MIN_ELEMENT 1
#define MAX_ELEMENT 1000000

int sum(int count, ...)
{
    va_list arr;
    int t = 0;
    va_start(arr, count);
    while(count--){
        t += va_arg(arr, int);
    }
    return t;
}

int min(int count, ...)
{
    va_list arr;
    int mn = MIN_ELEMENT;
    va_start(arr, count);
    while(count--){
        if(mn > va_arg(arr, int))
            mn = va_arg(arr, int);
    }
    return mn;
}

int max(int count, ...)
{
    va_list arr;
    int mx = MAX_ELEMENT;
    va_start(arr, count);
    while(count--){
        if(mx < va_arg(arr, int))
            mx = va_arg(arr, int);
    }
    return mx;
}

int test_implementations_by_sending_three_elements() {
    srand(time(NULL));
    
    int elements[3];
    
    elements[0] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[1] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[2] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    
    fprintf(stderr, "Sending following three elements:\n");
    for (int i = 0; i < 3; i++) {
        fprintf(stderr, "%d\n", elements[i]);
    }
    
    int elements_sum = sum(3, elements[0], elements[1], elements[2]);
    int minimum_element = min(3, elements[0], elements[1], elements[2]);
    int maximum_element = max(3, elements[0], elements[1], elements[2]);

    fprintf(stderr, "Your output is:\n");
    fprintf(stderr, "Elements sum is %d\n", elements_sum);
    fprintf(stderr, "Minimum element is %d\n", minimum_element);
    fprintf(stderr, "Maximum element is %d\n\n", maximum_element);
    
    int expected_elements_sum = 0;
    for (int i = 0; i < 3; i++) {
        if (elements[i] < minimum_element) {
            return 0;
        }
        
        if (elements[i] > maximum_element) {
            return 0;
        }
        
        expected_elements_sum += elements[i];
    }
    
    return elements_sum == expected_elements_sum;
}

int test_implementations_by_sending_five_elements() {
    srand(time(NULL));
    
    int elements[5];
    
    elements[0] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[1] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[2] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[3] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[4] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    
    fprintf(stderr, "Sending following five elements:\n");
    for (int i = 0; i < 5; i++) {
        fprintf(stderr, "%d\n", elements[i]);
    }
    
    int elements_sum = sum(5, elements[0], elements[1], elements[2], elements[3], elements[4]);
    int minimum_element = min(5, elements[0], elements[1], elements[2], elements[3], elements[4]);
    int maximum_element = max(5, elements[0], elements[1], elements[2], elements[3], elements[4]);
    
    fprintf(stderr, "Your output is:\n");
    fprintf(stderr, "Elements sum is %d\n", elements_sum);
    fprintf(stderr, "Minimum element is %d\n", minimum_element);
    fprintf(stderr, "Maximum element is %d\n\n", maximum_element);
    
    int expected_elements_sum = 0;
    for (int i = 0; i < 5; i++) {
        if (elements[i] < minimum_element) {
            return 0;
        }
        
        if (elements[i] > maximum_element) {
            return 0;
        }
        
        expected_elements_sum += elements[i];
    }
    
    return elements_sum == expected_elements_sum;
}

int test_implementations_by_sending_ten_elements() {
    srand(time(NULL));
    
    int elements[10];
    
    elements[0] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[1] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[2] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[3] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[4] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[5] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[6] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[7] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[8] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    elements[9] = rand() % (MAX_ELEMENT - MIN_ELEMENT + 1) + MIN_ELEMENT;
    
    fprintf(stderr, "Sending following ten elements:\n");
    for (int i = 0; i < 10; i++) {
        fprintf(stderr, "%d\n", elements[i]);
    }
    
    int elements_sum = sum(10, elements[0], elements[1], elements[2], elements[3], elements[4],
                           elements[5], elements[6], elements[7], elements[8], elements[9]);
    int minimum_element = min(10, elements[0], elements[1], elements[2], elements[3], elements[4],
                           elements[5], elements[6], elements[7], elements[8], elements[9]);
    int maximum_element = max(10, elements[0], elements[1], elements[2], elements[3], elements[4],
                           elements[5], elements[6], elements[7], elements[8], elements[9]);
    
    fprintf(stderr, "Your output is:\n");
    fprintf(stderr, "Elements sum is %d\n", elements_sum);
    fprintf(stderr, "Minimum element is %d\n", minimum_element);
    fprintf(stderr, "Maximum element is %d\n\n", maximum_element);
    
    int expected_elements_sum = 0;
    for (int i = 0; i < 10; i++) {
        if (elements[i] < minimum_element) {
            return 0;
        }
        
        if (elements[i] > maximum_element) {
            return 0;
        }
        
        expected_elements_sum += elements[i];
    }
    
    return elements_sum == expected_elements_sum;
}

int main ()
{
    int number_of_test_cases;
    scanf("%d", &number_of_test_cases);
    
    while (number_of_test_cases--) {
        if (test_implementations_by_sending_three_elements()) {
            printf("Correct Answer\n");
        } else {
            printf("Wrong Answer\n");
        }
        
        if (test_implementations_by_sending_five_elements()) {
            printf("Correct Answer\n");
        } else {
            printf("Wrong Answer\n");
        }
        
        if (test_implementations_by_sending_ten_elements()) {
            printf("Correct Answer\n");
        } else {
            printf("Wrong Answer\n");
        }
    }
    
    return 0;
}