HDOJ2050

HDACM2050

import java.util.Scanner;//把一条折线当做两条交叉的直线class Main{    public static void main(String args[]){        Scanner sc = new Scanner(System.in);        int c =sc.nextInt();        while(c-->0){            int n = sc.nextInt();            n = n*2; //把n条折线当做2n条交叉的直线            int sum = 2;            if (n==2) {                System.out.println(2);                continue;            }            for (int i = 2; i <= n; i++) {                if (n>2) {                    sum += i;                }            }            System.out.println(sum-n); //n条折线分割的面的个数比2n条直线分割的面的个数少2n个        }    }}