小白學JAVA-----P1001

[align=left]Problem Description[/align]
Hey, welcome to HDOJ(Hangzhou Dianzi University Online Judge).

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

 

[align=left]Input[/align]
The input will consist of a series of integers n, one integer per line.

 

[align=left]Output[/align]
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.

 

[align=left]Sample Input[/align]

1
100

 

[align=left]Sample Output[/align]

1

5050

 

[align=left]Author[/align]
DOOM III
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import java.util.Scanner;

class Main{

public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
while(sc.hasNext()){
int sum=0;
int a=sc.nextInt();
for(int i=1;i<=a;i++){
sum=sum+i;
}
System.out.println(sum);
System.out.println();
}
}

}
很简单的一道水题，意思就是 输入一个数，求这个数的前n项和，例如输入100就是1+2+3+··100；唯一需要注意的是每输出一个案例需要额外换一次行，这就是ACM，不容许一点错误
注意的是