## JadeEyes 3 years ago As a seasonal amusement some programmers like to print out a picture of a Christmas Tree looking like this. * *** * *** ***** * *** ***** ******* | ---+--- The tree consists of a series of tiers (three in this case) of increasing size. Write a program to produce such a display having prompted the user for thw number of tiers. You could try a few baubles on the tree (using o or O).

1. eSpeX

What language are you writing in, what have you already tried, and what is giving you difficulties?

I'm using C language..!! I have no difficulties with the language itself..!! It's the logic that I lack..!! :P ..!! I just can't figue out how to use loops to achieve the wanted result..!! Can you help me with that..?? :)..!!

3. experimentX

print characters 3 characters next time 5 characters .. 7 ... etc etc

4. experimentX

i haven't programmed C for very long time. do something like this for(i=1;i<= 3, i++) { for(k=2i+1; k >= 1; k++) { for(j=1; j<= 2i+1) { print on center here } } }

@eSpeX That's how tried doing it the first time using while loop : n = number of tiers while(n!=0) { printf( * \n) printf(O***O\n) n-- while(n!=0) { printf( * \n) printf( *** \n) printf( ***** \n) n-- } while(n!=0)...and so on..!! } But then it's kind of an infinite thing..!! ..@experimentX Thank you..!! However I don't really understand how it works..!!

6. experimentX

i don't seem to have c compiler in my computer .. mind if I send you python code?

I'll try to decode it back to C..!! :P ..!! So don't worry..!! :) ..!!

8. experimentX

i ended up codig this in java public class Christmas{ public static void main(String args[]){ int i, j, k; for(i=1; i <= 3; i++){ for(j=i+1; j>=1; j--){ for(k=1; k<=2*i+1; k++){ if(k >= j && k <= -j + 2*(i+1)) System.out.print("*"); else System.out.print(" "); } System.out.println(""); } } } }

9. experimentX

still not working

10. experimentX

this is the working code in Java public class Christmas{ public static void main(String args[]){ int i, j, k, l=3; for(i=1; i <= l; i++){ for(j=i+1; j>=1; j--){ for(int x=1; x<=l-i; x++) System.out.print(" "); for(k=1; k<=2*l+1; k++){ if(k >= j && k <= -j + 2*(i+1)) System.out.print("*"); else System.out.print(" "); } System.out.println(""); } } } }

The logic is that you want to build i triangles of heights j = 2, 3, 4, ... with row lengths k = 1, 3, 5, 7.... So you use nested for loops (go backwards starting with k).