Sum of First N Natural Numbers Using Recursion

Sum of First N Natural Numbers Using Recursion

Compute the sum of the first N natural numbers recursively.

Input format

A single integer N (1 ≤ N ≤ 800).

Output format

Print the sum 1 + 2 + … + N.

Constraints

• Values fit in a 64-bit signed integer
• Trailing whitespace and a trailing newline are ignored by the judge

Read from stdin, write to stdout. Sample cases below show the exact format.

1

1

2

3