C++ Program to Print the Pattern 'G"
In this article, we will learn how to print the pattern G using stars and white spaces. Given a number n, we will write a program to print the pattern G over n lines or rows.
Examples:
Input : 7 Output : *** * * * *** * * * * *** Input : 9 Output : ***** * * * * *** * * * * * * *****
In this program, we have used the simple logic of iteration over lines to create the pattern G. Please look at the image below which represents the pattern G in the form of a 2-d matrix, where mat[i][j] = 'ij':

If we try to analyze this picture with a (row, column) matrix and the circles represent the position of stars in the pattern G, we will learn the steps. Here we are performing the operations column-wise. So for the first line of stars, we set the first if condition, where the row position with 0 and (n-1) won't get the stars, and all other rows from 1 to (n-1), will get the stars. Similarly, for the second, third, and fourth columns, we want stars at the position row = 0 and row = (n-1). The other steps are self-explanatory and can be understood from the position of rows and columns in the diagram.
Example:
// C program to print the pattern G
#include <stdio.h>
void pattern(int line)
{
int i, j;
for (i = 0; i < line; i++) {
for (j = 0; j < line; j++) {
if ((j == 1 && i != 0 && i != line - 1)
|| ((i == 0 || i == line - 1) && j > 1
&& j < line - 2)
|| (i == ((line - 1) / 2) && j > 2
&& j < line - 1)
|| (j == line - 2 && i != 0
&& i >= ((line - 1) / 2)
&& i != line - 1))
printf("*");
else
printf(" ");
}
printf("\n");
}
}
int main()
{
int line = 7;
pattern(line);
return 0;
}
Output
*** * * * *** * * * * ***
Time Complexity: O(n2), where n represents the given input.
Auxiliary Space: O(1), no extra space is required, so it is a constant.