输出双层金字塔

#include <stdio.h>
int main()
{
int i,j,k,n,i2;
    while(scanf("%d", &n)!=EOF){
    for(i=1;i<=n;i++)
        {
        for(j=1;j<=n-i;j++) 
            printf(" ");
        for(k=1;k<2*i;k++)
            printf("*");
        printf("\n");
        }
    for(i2=1;i2<=n-1;i2++){
        for(j=1;j<=i2;j++)
        printf(" ");
        for(k=1;k<=2*(n-i2)-1;k++)
        printf("*");
        printf("\n");
    } 
    }
return 0;
}