C Program to Print Hollow Rectangle Star Pattern

How to write a C Program to Print Hollow Rectangle Star Pattern with example?. And also show you how to print a hollow rectangle pattern with different symbols.

C Program to Print Hollow Rectangle Star Pattern

This C program allows the user to enter the number of rows and columns to design a hollow rectangle. This value will decide the number of rows and columns of a hollow rectangle. Here, we are going to print the stars until it reaches the user-specified rows and columns.

/* C Program to Print Hollow Rectangle Star Pattern */
#include<stdio.h>
 
int main()
{
    int i, j, rows, columns;
     
    printf("Please Enter the Number of rows:\n");
    scanf("%d", &rows);
    
    printf("Please Enter the Number of Columns:\n");
    scanf("%d", &columns);
	 
    for(i = 0; i < rows; i++)
    {
        for(j = 0; j < columns; j++)
	{
	  if(i == 0 || i == rows-1 || j == 0 || j == columns-1)
	  {
		printf("*");
	  }
	  else
	  {
		printf(" ");
	  }          
        }
        printf("\n");
    }
    return 0;
}
C Program to Print Hollow Rectangle Star Pattern 1

Let us see the Nested for loop in the C Program to Print Hollow Rectangle Star Pattern example

for(i = 0; i < rows; i++)
{
   for(j = 0; j < columns; j++)
   {
     if(i == 0 || i == rows-1 || j == 0 || j == columns-1)
     {
	printf("*");
     }
     else
     {
	printf(" ");
     }          
   }
   printf("\n");
}

Outer Loop – First Iteration

From the above C Programming screenshot, you can observe that the value of i is 0 and Rows is seven so, the condition (i < 5) is True. So, it will enter into second for loop

Inner Loop – First Iteration

The j value is 0 and the condition (j < 15) is True. So, it will start executing the statement inside the loop. So, it will enter into the If Statement. Here, we are checking whether i = 0, j = 0, i = 6 (rows – 1) , or j = 14 (columns – 1). If any of this condition is true, then the following statement will print *. It means, Only the first column and last column in each row will print as output, and the remaining columns will print as an empty space.

printf("*");

It will happen until it reaches 7, and after that, both the Inner Loop and Outer loop will terminate.

C Program to Print Hollow Rectangle Pattern with Dynamic Character

This C program allows the user to enter the Symbol that he/she wants to print as a hallow rectangle pattern.

#include<stdio.h>
 
int main()
{
    int i, j, rows, columns;
    char Ch;
	
    printf("Please Enter any Symbol:  ");
    scanf("%c", &Ch);    
     
    printf("\nPlease Enter the Number of rows:  ");
    scanf("%d", &rows);
    
	printf("\nPlease Enter the Number of Columns:  ");
    scanf("%d", &columns);
	 
    for(i = 1; i <= rows; i++)
    {
        for(j = 1; j <= columns; j++)
	{
	  if(i == 1 || i == rows || j == 1 || j == columns)
	  {
		printf("%c", Ch);
	  }
	  else
	  {
		printf(" ");
	  }          
        }
        printf("\n");
    }
    return 0;
}
Please Enter any Symbol:  #

Please Enter the Number of rows:  10

Please Enter the Number of Columns:  20
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####################

About Suresh

Suresh is the founder of TutorialGateway and a freelance software developer. He specialized in Designing and Developing Windows and Web applications. The experience he gained in Programming and BI integration, and reporting tools translates into this blog. You can find him on Facebook or Twitter.