hdu 1001 Sum Problem(Java)

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.

代码

import java.util.Scanner;

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();
}

}

}