嚴格說這也是用到了if else
#include<stdio.h>
#define KG (n-i)
#define FH (n+i*2-2)
void main()
{
int i,j,n;
scanf("%d",&n);
for ( i=0;i<n;i++ )
{
?for ( j=0;j<KG;j++ ) printf(" "); ?printf("*"); ?for ( j=0;j<FH;j++ ) ( i==0 || i==n-1 )?printf("*"):printf(" "); ?printf("*"); ?printf("\n");}
}