triangle number

[kyle205]

Hey guys,

I am Kyle, kinda new here, I got problem with writing a program that will print triangle in screen;
0
010
01210
0123210
012343210
01234543210
0123456543210

here is what i got so far, i dont know how to write the number in each line

#include <stdio.h>

int main(void) {
	int num;
	printf ("Welcome to the Parymid program \n");
	printf ("Enter your number (1-9): ");
	scanf ("%d", &num);
	int i  ;
	int j ;
	
	for ( i = 0 ; i <= num ; i = i+1 ) {
		for ( j = 0 ; j <= i ; j = j+1 ) {
			printf ("%d ", j) ;
	        }
	printf ("\n");
	}
return 0;
}

Any ideas ??? please let me know

Thanks
Kyle Huynh

[kyle205]

by the way, that is not supposed to be right triangle

[Dino]

Start with asking yourself this question:

If a users enters a number, what is the maximum width of the longest line? When you get the answer for that, come up with (in math terms) a function that will calculate the maximum width.

[zacs7]

Note,

i = i+1

Can be written as

i++;

You've got the triangle there, just the lack of spaces have messed it up. A simple rule is, the next line should have 1 more space on the left than the previous. OR you could say, it has one less each time from the maximum line (see Dino's post).

That means the 2nd last line (at the bottom) has 1 more space on the left than the maximum line (the last line). The 3rd last line will have 2 more spaces than the last line, the 4th last line will have 3 more spaces than the last line. Eg:

0 
010
01210
0123210            ...
012343210          Should have N+2 spaces on the left
01234543210        Should have N+1 spaces on the left
0123456543210      Length of 'N' spaces on the left (none in this case)

Which ever way is easier for you to visualize, is the one you should use.