// Program4.c
// CSE 130 Fall 2009. Homework 4
// Drawing Triangles using functions, November 10th, 2009.
// Reza Basseda, Id-No: xxx-yy-zzzz


  #include <stdio.h>
  
  // Function prototypes/declarations:

  int topLine(int);

  void initialBlanks(int);

  int twoX(int);

  int bottom(void);

  int drawTriangle(int);


  int main(void)   // The main function called by operating functions.
   {
      int size, count;
        
      printf("Type in Triangle size: ");
      scanf("%d", &size);
        
      while (size != 0)     // The while condition checks termination.
        {
           count = drawTriangle(size);
           printf("Total number of O's and x's is %d.\n", count);
           printf("Type in Triangle size: ");
           scanf("%d", &size);
        }
      return 0;
   }


  int topLine(int n)    // This function draws the top line of triangle.
    {
       int i;
       printf("O");

        for(i=0; i<n; i++)
                printf(" x");

        printf(" O");
        printf("\n");
        
        return n+2;
     }

  void initialBlanks(int m) 

  // This function prints m initial blanks for the sides of triangle.
     {
	int i;
        for(i=0; i<m; i++)
                printf(" ");
      }

   int twoX(int k)      

  // This function draws sides of triangle. It prints 2 x's with
  // k blanks between them.
     {
        printf("x");

        for( ; k>0 ; k--)
                printf(" ");
        
        printf("x");
        printf("\n");
        return 2;
      }

   int bottom(void)     
   // This function draws the last vertex of triangle.
    {
        printf("O");
        return 1;
    }

   int drawTriangle(int n)

   // This function manages the printing of triangle.
     {
        int count = 0, i;
        printf("\n");   
        count = count + topLine(n);
        for(i=1; i<=n; i++)
          {
           initialBlanks(i);
           count = count + twoX(2*n-(2*i-1));  //(2n-1),(2n-2),etc...   
          }
         
        initialBlanks(n+1);
        count = count + bottom( );
        printf("\n\n");
        return count;
     }