triangleyang.java

打印杨辉三角的程序

import java.io.*;
/////////////////////////////////////////
public class TriangleYang
{
	public static int N;
	//------------------------------------
	TriangleYang(int n){
		N = n;
	}
	//---------------------------------------
	void Print(int n){
		int a[][] = new int[n][];
		for(int i=0;i<n;i++)
			a[i]=new int[i+1];
		for(int i=0;i<n;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];
		}
		
		System.out.println("The YangHui triangle is: ");
		for(int i=0;i<n;i++){
			for(int j=0;j<i+1;j++){
				System.out.print(a[i][j]+"\t");
				if(i==j)
				System.out.println();
			}
		}
	}
	//------------------------------------------------------
	public static void main(String[] args) throws IOException{
		System.out.println("Please input the n: ");
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		
		N=Integer.parseInt(br.readLine());
		
		TriangleYang yanghui=new TriangleYang(N);
		yanghui.Print(N);
	}
}