[C language practice - printing hollow square and its deformation]

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Preface

The front is already in 【C Language practice —— Print squares and their deformations 】、【C Language practice —— Print the hollow lower triangle and its deformation 】、【C Language practice —— Print the upper triangle of the hollow and its deformation 】 Honed printing hollow upper triangle and its deformation 、 Print hollow triangles and their deformations 、 Print squares and their deformations .

On this basis , Practice printing hollow squares and their deformations

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1、 Print a hollow square

1.1 graphics 1—— Blank free version

// Print a hollow square   No spaces 
int main()
{
    
	int n = 0;
	while (scanf("%d", &n) != EOF)
	{
    
		for (int i = 0; i < n; i++)// Row number 
		{
    
			for (int j = 0; j < n; j++)// Number of columns 
			{
    // Output when conditions are met  * , That is, on the boundary is  *
				if (i == 0 || j == 0 || i == n - 1 || j == n - 1)
					printf("*");
				else
					printf(" ");// All points not on the boundary are spaces  
			}
			printf("\n");
		}
	}
	
	return 0;
}

The results are as follows ：

1.2 graphics 2—— Blank version

// Print a hollow square   Blank Edition 
int main()
{
    
	int n = 0;
	while (scanf("%d", &n) != EOF)
	{
    
		for (int i = 0; i < n; i++)// Row number 
		{
    
			for (int j = 0; j < n; j++)// Number of columns 
			{
    // Output when conditions are met  * , That is, on the boundary is  *
				if (i == 0 || j == 0 || i == n - 1 || j == n - 1)
					printf("* ");
				else
					printf(" ");// All points not on the boundary are spaces  
			}
			printf("\n");
		}
	}

	return 0;
}

The results are as follows ：

1.3 graphics 3—— rotate 45 degree , No blank space version

// Print a square , rotate 45 degree , No blank space version 
int main()
{
    
	int n = 0;
	while (scanf("%d", &n) != EOF)
	{
    
		// Print the top half  n
		for (int i = 0; i < n; i++)
		{
    
			// Print a row 
			// Print space 
			int j = 0;
			for (j = 0; j < n - 1 - i; j++)
			{
    
				printf(" ");
			}
			// Print *
			for (j = 0; j < 2 * i + 1; j++)
			{
    // Output when conditions are met  * , That is, on the boundary is  *
				if (j == 0 || j == 2 * i )
					printf("*");
				else
					printf(" ");// All points not on the boundary are spaces 
			}
			printf("\n");
		}
		// Print the bottom half  n-1
		for (int i = 0; i < n - 1; i++)
		{
    
			// Print a row 
			// Print space 
			int j = 0;
			for (j = 0; j <= i; j++)
			{
    
				printf(" ");
			}
			// Print *
			for (j = 0; j < (n - 1 - i) * 2 - 1; j++)
			{
    // Output when conditions are met  * , That is, on the boundary is  *
				if (j == 0 || j == (n - 1 - i) * 2 - 2)
					printf("*");
				else
					printf(" ");// All points not on the boundary are spaces  
			}
			printf("\n");
		}
		
	}
	return 0;
}

The results are as follows ：

1.4 graphics 4—— rotate 45 degree , Blank version

// Print a square , rotate 45 degree , Blank version 
int main()
{
    
	int n = 0;
	while (scanf("%d", &n) != EOF)
	{
    
		// Print the top half  n
		for (int i = 0; i < n; i++)
		{
    
			// Print a row 
			// Print space 
			int j = 0;
			for (j = 0; j < n - 1 - i; j++)
			{
    
				printf(" ");
			}
			// Print *
			for (j = 0; j <= i; j++)
			{
    // Output when conditions are met  * , That is, on the boundary is  *
				if (j == 0 || i == j)
					printf("* ");
				else
					printf(" ");// All points not on the boundary are spaces 
			}
			printf("\n");
		}
		// Print the bottom half  n-1
		for (int i = 0; i < n - 1; i++)
		{
    
			// Print a row 
			// Print space 
			int j = 0;
			for (j = 0; j <= i; j++)
			{
    
				printf(" ");
			}
			// Print *
			for (j = 0; j < (n - 1 - i); j++)
			{
    // Output when conditions are met  * , That is, on the boundary is  *
				if (j == 0 || j == n - i - 2)
					printf("* ");
				else
					printf(" ");// All points not on the boundary are spaces  
			}
			printf("\n");
		}
	}
	
	return 0;
}
}

The results are as follows ：

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summary

This article exercises printing hollow square and its deformation , Mainly practice ：

• Outer loop 、 Application of internal circulation
• Pay attention to the number of lines 、 Space number 、 Symbol * Mathematical expressions between numbers

Active address ： Graduation season · The technique of attack er