java实现打印菱形

package cn.jbit.nestedloops;
import java.util.Scanner;
/**
 * 输入行数打印菱形
 */
public class Diamond {
	public static void main(String[] args) {
		int rows = 0;	//菱形的行数
		Scanner input = new Scanner(System.in);
		System.out.print("请输入菱形行数：");
		rows = input.nextInt();

		while(rows%2 == 0){
			System.out.print("请输入奇数：");
			rows = input.nextInt();
		}

		int n = (rows+1)/2;
		//打印菱形的上半部分
		for(int i = 1; i <= n; i++){//外层循环变量i控制行数
			for(int j = 1; j <= n-i; j++){//内层循环变量j控制该行空格数
				System.out.print(" ");
			}
			for(int k = 1; k <= 2*i-1; k++){//内层循环变量k控制该行*号数
				System.out.print("*");
			}
			System.out.print("\n");
		}
		//打印菱形的下半部分
		for(int i = n-1; i >= 1; i--){
			for(int j = 1; j <= n-i; j++){
				System.out.print(" ");
			}
			for(int k = 1; k <= 2*i-1; k++){
				System.out.print("*");
			}
			System.out.print("\n");
		}
	}
}