Write a c Program for Pyramid ?

Question

                                      *
                                     * *
                                    * * *
                                   * * * *
                                  * * * * * 
                                 * * * *     

I above Ouput I Missed two stars.My question is how to find out the remaining stars.Please tel me in the C programming way.

Comments

If you know that it is a pyramid and know the number of rows say in this case 6 then number of total stars are n*(n+1)/2 i.e. 21. Just count the number of * and subtract from 21 will give you number of missing stars.

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Hi

Can you explain with program Logic.I am bit confuse.

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Its simple ur first row will have 1 star, 2nd will have 2 and nth wil have n stars.
Now its a case of 1+2+3...n problem which is n*(n+1)/2...

Answer 1

#include<stdio.h>
#include<conio.h>
int main()
{
 int num,r,c,sp,x;
 printf("Enter loop repeat number(rows):");
 scanf("%d",&num);
 for(r=1; num>=r; r++)
 {
   for(sp=num-r; sp>=1; sp--)
      printf(" ");
   for(c=1; c<=r; c++)
      printf("%d",c);
   for(x=r-1; x>=1; x--)
      printf("%d",x);
   printf("\n");
 }
 getch();
 return 0;
} 

Comments

I tested this code and it prints for num=5
     1
   121
  12321
 1234321
123454321

Where question is different then this....

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before giving answer pls check my question.