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; }

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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