Sum Problem
Time Limit: 1000/500 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 140390 Accepted Submission(s): 32755
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
1 100
Sample Output
1 5050
Author
package endual;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner cin = new Scanner(System.in) ;
long sum = 0 ;
int n = 0 ;
while(cin.hasNextInt()){
n = cin.nextInt();
sum = digui(n) ;
System.out.println(sum + "\n\n");
}
}
private static long digui(int n) {
if (1 == n) {
return 1 ;
}
return n + digui(n-1) ;
}
}
不知道是为什么要两个斜杠，我知道这是说明的是换行
