C Programs to calculate the sum of the elements in an array have been shown here. The following section also covers the algorithm, pseudocode and time complexity of the program.
Page content(s):
1. Algorithm to calculate the sum of the elements in an array
1. Take input of an array A[] and the size n
2. Set i = 0 and sum = 0
3. Perform sum = sum + A[i]
4. Perform i = i + 1.
5. If i < n, go to step 3 else display sum as the result.
2. Pseudocode to calculate the sum of the elements in an array
Input: An array $A[~]$ and size of array $n$
Output: Sum of the elements in $A[~]$
1. Procedure arraySum($A[~]$, $n$):
2.
3.
4.
5.
6. End Procedure
3. Time complexity to calculate the sum of the elements in an array
Time Complexity: O(n)
Where n is the total no of elements in the array.
4. C Program & output to calculate the sum of the elements in an array using iteration
/******************************* alphabetacoder.com C program to calculate the sum of the elements using iteration *********************************/ #include <stdio.h> int main() { // declare an array int arr[5] = {10, 20, 30, 40, 50}; // declare variables int i, sum; // initialize variable sum = 0; // add an element to sum in each iteration for (i = 0; i < 5; i++) { sum = sum + arr[i]; } // display result printf("Total sum = %d", sum); return 0; }
Output
Total sum = 150
5. C Program & output to calculate the sum of the elements in an array using recursion
/******************************* alphabetacoder.com C program to calculate the sum of the elements using recursion *********************************/ #include <stdio.h> // recursive function to find // sum of elements in array int find_sum(int arr[], int sum, int i){ // exit condition if(i < 0) return sum; // add current element to sum sum = sum + arr[i]; // call function return find_sum(arr, sum, i - 1); } int main(){ // declare an array int arr[5] = {15, 25, 35, 45, 55}; // declare variables int min, length, sum; // calculate size of array length = sizeof(arr)/sizeof(arr[0]); // initialize variable sum = 0; // call function to get the // sum of elements as return value // pass the array, sum = 0 and the // size of the array sum = find_sum(arr, 0, length - 1); // display result printf("Total sum = %d", sum); return 0; }
Output
Total sum = 150