C Exercises: Find the sum of all elements of an array

C Array: Exercise-3 with Solution

Write a program in C to find the sum of all elements of an array.

Visual Presentation:

Sample Solution:

#include <stdio.h>
// Main function
int main()
{
    int a[100];  // Declare an array of size 100 to store integer values
    int i, n, sum = 0;  // Declare variables to store array size, loop counter, and sum
    // Display a message to the user about the program's purpose
    printf("\n\nFind sum of all elements of array:\n");
    printf("--------------------------------------\n");	
    // Prompt the user to input the number of elements to be stored in the array
    printf("Input the number of elements to be stored in the array :");
    scanf("%d", &n);
    // Prompt the user to input n elements into the array
    printf("Input %d elements in the array :\n", n);
    for (i = 0; i < n; i++)
    {
        printf("element - %d : ", i);
        scanf("%d", &a[i]);  // Read the input and store it in the array
    }

    // Calculate the sum of all elements in the array using a for loop
    for (i = 0; i < n; i++)
    {
        sum += a[i];  // Add each element to the sum
    }
    // Display the sum of all elements stored in the array
    printf("Sum of all elements stored in the array is : %d\n\n", sum);
	return 0;
}

Sample Output:

Find sum of all elements of array:                                                                            
--------------------------------------                                                                        
Input the number of elements to be stored in the array :3                                                     
Input 3 elements in the array :                                                                               
element - 0 : 2                                                                                               
element - 1 : 5                                                                                               
element - 2 : 8                                                                                               
Sum of all elements stored in the array is : 15 

Explanation:

  printf("Input the number of elements to be stored in the array :");
       scanf("%d",&n);
   
       printf("Input %d elements in the array :\n",n);
       for(i=0;i<n;i++)
        {
	      printf("element - %d : ",i);
	      scanf("%d",&a[i]);
	    }

    for(i=0; i<n; i++)
    {
        sum += a[i];
    }

    printf("Sum of all elements stored in the array is : %d\n\n", sum);

In the above code -

• The first printf statement prompts the user to input the number of elements they want to store in the array and stores it in the variable n using scanf.
• The second printf statement asks the user to input n number of elements into the array using a for loop, and stores each input in the corresponding index of the array a[i].
• The third for loop calculates the sum of all the elements in the array by iterating over each element of the array and adding its value to the variable sum.
• The final printf statement then prints out the sum of all the elements in the array using the value stored in the variable sum.

Flowchart :

C Programming Code Editor:

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