« Print the sum of all elements of the array recursively.

Problem:

Calculate the sum of all elements of the array recursively.

Input Format :

Line 1 : An Integer N i.e. size of array

Line 2 : N integers which are elements of the array, separated by spaces

Output Format :

Print sum of the array

Constraints :

1 <= N <= 10^3

Sample Input 1 :

3 9 8 9

Sample Output 1 :

26

Sample Input 2 :

3 4 2 1

Sample Output 2 :

7

Solution:

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1#include <iostream>
2#include <iomanip>
3#include <algorithm>
4#include <string>
5#include <cstring>
6#include <vector>
7#include <cmath>
8#include <map>
9#include <climits>
10// climits for INT_MIN
11#include <unordered_map>
12using namespace std;
13
14int sum2(int input[], int n)
15{
16    if (n == 0)
17    {
18        return 0;
19    }
20    return (input[0] + sum2(input + 1, n - 1));
21}
22
23int sum(int input[], int n)
24{
25    if (n == 1)
26    {
27        return input[0];
28    }
29    return (input[0] + sum(input + 1, n - 1));
30}
31int main()
32{
33    int n;
34    cin >> n;
35
36    int *input = new int[n];
37
38    for (int i = 0; i < n; i++)
39    {
40        cin >> input[i];
41    }
42
43    cout << sum(input, n) << endl;
44    cout << sum2(input, n) << endl;
45    return 0;
46}