请JAVA高手进来，一道小编程题。答对再加50分。

public class SumUp
{
public static void main (String[] args)
{
int sum = 0;
for (int i=1; i<=100; i++) // n = 100
{
sum += i;
}
System.out.println ("The sum is: " + sum);
}
}

输出:
The sum is: 5050

public class Sum {

public Sum()
{
System.out.println(this.getSum(200)); //这里的200为n,
}
private int getSum(int c)
{
if(c == 1)
return c;
else
return c + this.getSum(c - 1);

}

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
new Sum();
}

import java.util.Scanner;
public class testfor1 {
public static void main(String[] args){
int sum=0;
Scanner scanner = new Scanner(System.in);
System.out.println("请输入N:"