杨辉三角

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace yanghuisanjiao
{
    class Program
    {
        static void Main(string[] args)
        {
            //方法一：
            int[,] a = new int[5, 5];
            a[0, 0] = 1;
            for (int i = 1; i < 5; i++)
            {
                a[i, 0] = 1;
                a[i, i] = 1;
                for (int j = 1; j < i; j++)
                {
                    a[i, j] = a[i - 1, j - 1] + a[i - 1, j];
                }
            }
            for (int i = 0; i < 5; i++)
            {

                for (int k = 0; k < 31 - 2 * i; k++)      //对输出格式处理
                    Console.Write(" ");

                for (int j = 0; j <= i; j++)
                {
                    Console.Write("  {0} ", a[i, j]);
                }
                Console.WriteLine();
            }
            Console.ReadLine();

            //方法二：
            Console.WriteLine("请输入一个整数：");
            int n=int.Parse(Console.ReadLine());
            int[,] number=new int[n,n];
            number[0, 0] = 1;
            for (int i = 1; i < n; i++)
            {
                number[i, 0] = 1;
                number[i, i] = 1;
                for (int j = 1; j <i; j++)
                {
                    number[i, j] = number[i - 1, j-1] + number[i - 1, j];
                }
               
            }
            for (int m = 0; m < n; m++)
            {
                for (int k = 0; k < m; k++)
                {
                    Console.Write(number[m, k] + " ");
                }
                Console.WriteLine();
            }
              
            Console.ReadLine();

        }
    }
}