c++
#include<bits/stdc++.h> using namespace std; int main(){ int a; while(cin>>a){ for(int i=0;i<a+1;i++){ for(int j=a;j>i;j--){ cout<<" "; } for(int k=-1;k<i;k++){ cout<<"* "; } cout<<endl; } for(int m=0;m<a;m++){ for(int n=0;n<=m;n++){//没写等号 cout<<" "; } for(int p=a;p>m;p--){ cout<<"* "; } cout<<endl; } } } //for循环的数量；java:
import java.io.*; public class Main{ public static void main(String[]args)throws IOException{ BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); String s; while((s=br.readLine())!=null){ int a=Integer.parseInt(s); for(int i=0;i<a+1;i++){ for(int j=0;j<a-i;j++){ System.out.printf(" "); } for(int j=0;j<=i;j++){ System.out.printf("* "); } System.out.printf("\n"); } for(int i=0;i<a;i++){ for(int j=0;j<=i;j++){ System.out.printf(" "); } for(int j=0;j<a-i;j++){ System.out.printf("* "); } System.out.printf("\n"); } } } }