Pattern Programmings - c

Question

I am having difficulty understanding the logic behind drawing patterns with * and numbers in C.
For example, I am drawing this pattern:
*
* *
** **
* *
*
Some things that I understand in this programs are to take various for loops for printing * and whitespaces, but it's getting difficult to determine the conditions for them.
In the above example I think I need to draw half the triangle and the remaining is the reverse of it.
So please help me to understand the logic I should consider to draw such patterns every time.
#include<stdio.h>
#include<conio.h>
void main()
{
int i,j=0,k,l,m,o,n=6;
clrscr();
printf(" ");
for(i=0;i<=3;i++)
{
for(j=2;j>0;j--)
{
printf(" ");
for(k=0;k<=(2*i);k++)
{
printf("*");
// getch();
}
}
// getch();
printf("\n");
}
getch();
}
This is how I tried coding, I am not getting the conditions for nested for loop.

Answer 1

-2 -1 0 1 2
+---+---+---+---+---+
-2 | . | . | X | . | . |
+---+---+---+---+---+
-1 | . | X | O | X | . |
+---+---+---+---+---+
0 | X | X | O | X | X |
+---+---+---+---+---+
1 | . | X | O | X | . |
+---+---+---+---+---+
2 | . | . | X | . | . |
+---+---+---+---+---+
Points are not drawn if (col = 0 and abs(row) != 2) or either row or col is 2 and other is non-zero. You can implement these conditions in your code.
For(row = -2 to 2)
For(col = -2 to 2)
if ( (col = 0 and abs(row) != 2) or (abs(row) = 2 and col != 0) or (abs(col) = 2 and row != 0) )
draw space character
else
draw *
line break

Answer 2

#include<stdio.h>
#include<conio.h>
int main()
{
int n=3,i,j,k,l,m;
clrscr();
for(i=0;i<n;i++)
{
for(j=0;j<n-i-1;j++)
printf(" ");
for(k=0;k<=i-1;k++)
printf("*",k+1);
for(m=0;m<1;m++)
{
if(i<=0)
printf("*");
else
printf(" ");
}
for(l=i-1;l>=0;l--)
printf("*",l+1);
printf("\n");
}
for(i=0;i<n-1;i++)
{
for(j=0;j<=i;j++)
printf(" ");
for(k=0;k<n-i-2;k++)
printf("*",k+1);
for(m=0;m<1;m++)
{
if(i==1)
{}
else
printf(" ");
}
for(l=1;l>0;l--)
printf("*",l+1);
printf("\n");
}
getch();
return 0;
}
Finally I got my solution by myself.