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 elements and perform addition

#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\n");
 scanf("%d", &Size);
 
 printf("\nPlease Enter the 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, and add every item to Addition 
 for(i = 0; i < Size; i ++)
 {
      Addition = Addition + a[i]; 
 }
  
 printf("Sum = %d ", Addition);
 return 0;
}

C sum of array items using a for loop output


 Please Enter the Size
4

Please Enter the Elements
10
20
30
40
Sum = 100 

We already explained the program flow in Perform Arithmetic Operations on One Dimensional 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

#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 example 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