Problem:
Score : 100 points

Problem Statement

There are N children in AtCoder Kindergarten. Mr. Evi will arrange the children in a line, then give 1 candy to the first child in the line, 2 candies to the second child, ..., N candies to the N-th child. How many candies will be necessary in total?

Constraints

1≦N≦100

Input

The input is given from Standard Input in the following format:

N

Output

Print the necessary number of candies in total.

Sample Input 1

3

Sample Output 1

6

The answer is 1+2+3=6.

Sample Input 2

10

Sample Output 2

55

The sum of the integers from 1 to 10 is 55.

Sample Input 3

1

Sample Output 3

1

Only one child. The answer is 1 in this case.

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int func(int a)
{
	if (a == 1)
	{
		return 1;
	}
	else {
		return func(a - 1)+a;
	}
}


int main()
{
	int num, ans;
	//階乗を求める
	printf("自然数だけよ♡");
	scanf("%d", &num);
	ans = func(num);
	printf("あ～、答えの音～: %d\n",ans);
	return 0;
}