C :

#include<stdio.h> 


int main(){ 
	int n,i,j,z;
	scanf("%d",&n);
	//控制输出的行数 
	for(i = n;i >= 1;i-=2){
		//控制每行输出空格量 
		for(j = 0;j < (n-i) / 2;j++){
			printf(" "); 
		}
		//控住输出的*
		for(z=1;z <= i;z++){
			printf("*");
		} 
		//负责换行 
		printf("\n");
	}
	
	for(i = 3;i <= n;i+=2){
		//控制每行输出空格量 
		for(j = 0;j < (n-i) / 2;j++){
			printf(" "); 
		}
		//控住输出的*
		for(z=1;z <= i;z++){
			printf("*");
		} 
		//负责换行 
		printf("\n");		
	} 

	
	return n; 
} 

C++ :

#include<iostream>
using namespace std;

int main(){
	int i,j,n,y,x;
	cin>>n;
	n=(n+1)/2;
	//ÕýÈý½Ç 
	for(i=n;i>=1;i--){
		if(i==1){
			
		}else{
			for(j=1;j<=n-i;j++){
			cout<<" ";
			
		    } 
		}
		
		if(i==1){
			
		}else{
			for(j=1;j<=2*i-1;j++){
			cout<<"*";
		    }
		}
		
		if(i==1){
			
		}else{
			cout<<endl;
		}
		
		
	} 
	for(i=1;i<=n;i++){
		for(j=1;j<=n-i;j++){
			cout<<" ";
			
		}
		for(j=1;j<=2*i-1;j++){
			cout<<"*";
		}
		cout<<endl;
	}
	
} 

Python :

n = int(input());  
for i in range(1, n//2 +1 ):
    for k in range(1, i):
      print(end=' ')
    for x in range(1 ,n - (i -1)*2+1):
        print('*', end = '')
    print()
for a in range (1, n//2 + 2 ):
    for b in range (1, n // 2 +1 - a + 1 ):
        print('',end=' ')
    for c in range (1, 2*a ):
        print('*' ,end='')
    print()