C Program to find Sum of all Elements in an Array

How to write a C Program to find Sum of all Elements in an Array using For Loop, While Loop, Functions with example.

C Program to find Sum of all Elements in an Array

This C program allows the user to enter the Size and number of rows for One Dimensional Array. Next, we are using the For Loop to iterate the array values and perform addition

// C Program to find Sum of all Elements in an Array
#include<stdio.h>

int main()
{
 int Size, i, a[10];
 int Addition = 0;
 
 // You have specify the array size 
 printf("\n Please Enter the Size of the Array\n");
 scanf("%d", &Size);
 
 printf("\nPlease Enter the Array Elements\n");
 //Start at 0, it will save user enter values into array a 
 for(i = 0; i < Size; i++)
  {
      scanf("%d", &a[i]);
  }
 // Loop Over Array, and add every array item to Addition 
 for(i = 0; i < Size; i ++)
 {
      Addition = Addition + a[i]; 
 }
  
 printf("Sum of All Elements in an Array = %d ", Addition);
 return 0;
}

C sum of array items using a for loop output


 Please Enter the Size of the Array
4

Please Enter the Array Elements
10
20
30
40
Sum of All Elements in an Array = 100 

We already explained the program flow in Perform Arithmetic Operations on One Dimensional Array article. So, I suggest you refer the same in C Programming for better understanding.

Program to find Sum of all Elements in an Array using While Loop

This C program is the same as above, but this time we used While Loop to perform the One Dimensional Array addition

// C Program to find Sum of all Elements in an Array using While Loop
#include<stdio.h>

int main()
{
 int i, Size, a[10];
 int j = 0, Addition = 0;
  
 printf("Please Enter the Size of an Array: ");
 scanf("%d", &Size);
 
 printf("\nPlease Enter Array Elements\n");
 for(i = 0; i < Size; i++)
  {
      scanf("%d", &a[i]);
  }
  
 while(j < Size )
  {
      Addition = Addition + a[j]; 
      j++; 
  }
  
 printf("Sum of All Elements in an Array = %d ", Addition);
 return 0;
}
Please Enter the Size of an Array: 7

Please Enter Array Elements
10
20
30
40
50
60
90
Sum of All Elements in an Array = 300 

Program to find Sum of all Elements in an Array using Functions

This C program is the same as the first example, but this time we used Functions to perform addition

// C Program to find Sum of all Elements in an Array using Function
#include<stdio.h>
int SumofNumbers(int a[], int Size);
int main()
{
 int i, Size, a[10];
 int Addition;
  
 printf("Please Enter the Size of an Array: ");
 scanf("%d", &Size);
 
 printf("\nPlease Enter Array Elements\n");
 for(i = 0; i < Size; i++)
  {
      scanf("%d", &a[i]);
  }
  
  Addition = SumofNumbers(a, Size);

  
 printf("Sum of All Elements in an Array = %d ", Addition);
 return 0;
} 
int SumofNumbers(int a[], int Size)
{
	int Addition = 0;
	int i;
 	for(i = 0; i < Size; i++)
 	{
      Addition = Addition + a[i]; 
 	}
	 return Addition;	
}
C Program to find Sum of all Elements in an Array 3