Sum of all Nodes

Iterative and recursive way of finding the sum of data of all the nodes in a linked list.

Iterative Method :

int sum(struct node *ptr) {
​
// A variable to keep track of sum
int sum = 0;
// Iterate till ptr becomes NULL
while (ptr != NULL) {
sum += ptr -> data;
ptr = ptr -> next;
}
return sum;
}

Recursive Method :

int sum(struct node *ptr) {
​
// Base condition for termination
if (p == NULL) {
return 0;
}
// Recursive call
else {
return sum(ptr -> next) + p -> data;
}
​
}

Time and Space Complexity :

Iterative
Recursive
Time complexity : O(n) Space complexity : O(n)
Time complexity : O(n) Space complexity : O(1)
Contributed by Nitin Ranganath