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 main()
{
	int i, n;
	int sum=0;
	scanf("%d", &n);
	if(n>=1&&n<=100)
	{
	for(i=1;i<=n;i++)
	sum+=i;
}
	printf("%d\n",sum);
	if(sum == 6)
	printf("The answer is 1 + 2 + 3 = 6.");
	if(sum == 55)
	printf("The sum of the integers from 1 to 10 is 55.");
	if(sum == 1)
	printf("Only one child. The answer is 1 in this case.");
	return 0;
}