HDOJ1001：Sum Problem

Problem Description

Hey, welcome to HDOJ(Hangzhou Dianzi University Online Judge).

In this problem, your task is to calculate SUM(n) = 1 + 2 + 3 + ... + n.

 

Input

The input will consist of a series of integers n, one integer per line.

 

Output

For each case, output SUM(n) in one line, followed by a blank line. You may assume the result will be in the range of 32-bit signed integer.

 

Sample Input

1100

 

Sample Output

15050
Java Code：
import java.util.Scanner;public class Main {public static void main(String[] args){Scanner sc=new Scanner(System.in);while(sc.hasNext()){int n=sc.nextInt();int sum=0;for(int i=1;i<=n;i++){sum+=i;}System.out.println(sum);System.out.println();}}}