Replay the snake game with C language (II) end

Take the book back , We reproduced the snake page , The next step is to reproduce the operation of the game ：

// Mobile small snake 
// The first step is to scan the array canvas All elements of , Find positive elements and add 1
// Find the largest element （ Snake tail ）, Turn it into 0
// Find something equal to 2 The elements of （ Snakehead ）, Set the corresponding other pixel value as 1（ New snake head ） 
void moveSnakeByDirection()
{
	int i,j;
	for(i=1;i<High-1;i++)
	  for(j=1;j<Width-1;j++)
	    if(canvas[i][j]>0)
	    canvas[i][j]++;
	    
	    
	int oldTail_i,oldTail_j,oldHead_i,oldHead_j;
	int max = 0;
	
	for(i=1;i<High-1;i++)
	  for(j=1;j<Width-1;j++)
	    if(canvas[i][j]>0)
	{
		if(max<canvas[i][j])
		{
			max = canvas[i][j];
			oldTail_i =i;
			oldTail_j =j;
		}
		if(canvas[i][j]==2)
		{
			oldHead_i = i;
			oldHead_j = j;
		}
    }
int newHead_i,newHead_j;	

if(moveDirection==1)          //   Move up  
   {
   newHead_i = oldHead_i-1;
   newHead_j = oldHead_j;
}
if(moveDirection==2)          //   Move down the  
  {
   newHead_i = oldHead_i+1 ;
   newHead_j = oldHead_j;
}
if(moveDirection==3)          //   Move to the left  
  {
    newHead_i = oldHead_i ;
   newHead_j = oldHead_j-1;
}
if(moveDirection==4)          //   To the right  
   {newHead_i = oldHead_i ;
   newHead_j = oldHead_j + 1;		 
}

Add this line of code to realize the movement of the snake .

// If the new snake head eats food  
if(canvas[newHead_i][newHead_j] == -2)
{
	canvas[food_x][food_y] = 0;    // Produce a new food 
	food_x = rand()%(High-5) +2;
	food_y = rand()%(Width-5) +2;
	canvas[food_x][food_y] = -2 ;  // The original Snake tail is left , The length is automatically increased 1 
}
else                              // otherwise , The original old snake tail is lost , Keep the length constant 
  canvas[oldTail_i][oldTail_j] = 0;
  

These are a reproduction of the classic rules of the game ： Presence of food , The length of the snake's tail increases when it eats food .

// Whether the snake collides with itself or with the frame . The game failed 
if(canvas[newHead_i][newHead_j]>0||canvas[newHead_i][newHead_j]==-1)
{
	printf(" The game failed ！\n");
	Sleep(2000);
	system("pause");
	exit(0);
 } 
 else
 canvas[newHead_i][newHead_j] = 1;
 
}

This is the judgment of game failure , When the snake collides with itself and the wall, it is determined that the game has failed .

	else if(canvas[i][j]==-2)
			printf("F");                  // Export food  F 

Insert this code into （ One ） in viod show Inner loop in function for At the back of .（ All the code will be presented at the end of the article ）

void updateWithoutTnput()             // User independent updates  
{
  moveSnakeByDirection();
}
void updateWithInput()               // User related updates  
{
	char input;
	if(kbhit())                      // Determine if there is input  
	{
		input=getch();               // Move according to the user's different input , Enter not required 
		if(input =='a')
		{
			moveDirection = 3;       // Position left  
			moveSnakeByDirection();
		}
		else if (input=='d')
		{
			moveDirection =4;               // Position right 
			moveSnakeByDirection();         
		}
		else if(input=='w')
		{
			moveDirection =1;              // Move the position up  
			moveSnakeByDirection();
		}
		else if (input=='s')
		{
			moveDirection =2;              // Position down  
			moveSnakeByDirection();
		 } 
	}	
}

These functions enable the player to control the snake .

The above description is not complete , The following is the full code of this suggested Snake game ：

#include<stdio.h>
#include<stdlib.h>              // Contains C、C++ The most commonly used system function of language 
#include<conio.h>               // It is mainly the input and output of files and standard console 
#include<windows.h>             // Control page  

#define High 20                 // Game screen size  ： high 20. wide 30 
#define Width 30


//0 Is a space ,-1 Is border #,1 For the snake head @, Greater than 1 For the snake                      
int canvas[High][Width]={0};       // Two dimensional array   Store elements  
int moveDirection; 
int food_x,food_y;
	   
void gotoxy(int x,int y)          // Move the cursor to （x,y）; Included in conio.h    
{
	HANDLE handle= GetStdHandle(STD_OUTPUT_HANDLE);
	COORD pos; 
	pos.X=x;
	pos.Y=y;
	SetConsoleCursorPosition(handle,pos);
}




// Mobile small snake 
// The first step is to scan the array canvas All elements of , Find positive elements and add 1
// Find the largest element （ Snake tail ）, Turn it into 0
// Find something equal to 2 The elements of （ Snakehead ）, Set the corresponding other pixel value as 1（ New snake head ） 
void moveSnakeByDirection()
{
	int i,j;
	for(i=1;i<High-1;i++)
	  for(j=1;j<Width-1;j++)
	    if(canvas[i][j]>0)
	    canvas[i][j]++;
	    
	    
	int oldTail_i,oldTail_j,oldHead_i,oldHead_j;
	int max = 0;
	
	for(i=1;i<High-1;i++)
	  for(j=1;j<Width-1;j++)
	    if(canvas[i][j]>0)
	{
		if(max<canvas[i][j])
		{
			max = canvas[i][j];
			oldTail_i =i;
			oldTail_j =j;
		}
		if(canvas[i][j]==2)
		{
			oldHead_i = i;
			oldHead_j = j;
		}
    }
int newHead_i,newHead_j;	

if(moveDirection==1)          //   Move up  
   {
   newHead_i = oldHead_i-1;
   newHead_j = oldHead_j;
}
if(moveDirection==2)          //   Move down the  
  {
   newHead_i = oldHead_i+1 ;
   newHead_j = oldHead_j;
}
if(moveDirection==3)          //   Move to the left  
  {
    newHead_i = oldHead_i ;
   newHead_j = oldHead_j-1;
}
if(moveDirection==4)          //   To the right  
   {newHead_i = oldHead_i ;
   newHead_j = oldHead_j + 1;		 
}

 
// If the new snake head eats food  
if(canvas[newHead_i][newHead_j] == -2)
{
	canvas[food_x][food_y] = 0;
	// Produce a new food 
	food_x = rand()%(High-5) +2;
	food_y = rand()%(Width-5) +2;
	canvas[food_x][food_y] = -2;
	// The original Snake tail is left , The length is automatically increased 1 
}
else                          // otherwise , The original old snake tail is lost , Keep the length constant 
  canvas[oldTail_i][oldTail_j] = 0;
  
  
  
  
// Whether the snake collides with itself or with the frame . The game failed 
if(canvas[newHead_i][newHead_j]>0||canvas[newHead_i][newHead_j]==-1)
{
	printf(" The game failed ！\n");
	Sleep(2000);
	system("pause");
	exit(0);
 } 
 else
 canvas[newHead_i][newHead_j] = 1;
 
}
 
void startup()                // Initialization of data  
{
	int i,j;
	
	// Initialize border  
	for(i=0;i<High;i++)
	{
		canvas[i][0]=-1;              //[a][b] The first a-1 That's ok , The first b-1 Column  
		canvas[i][Width-1] = -1;
	} 
	for(j=0;j<Width;j++)
	{
		canvas[0][j] = -1;
		canvas[High-1][j]= -1;		
	}
	
	
	// Initialize snakehead position 
	canvas[High/2][Width/2]=1;
	//  Initialize the snake body , The element value in the canvas is 2,3,4,5 etc. 
	for (i=1;i<=4;i++) 
	 canvas[High/2][Width/2-i]=i+1;

	// The initial snake moves to the right 
    moveDirection=4;
	
	food_x = rand()%(High-5) + 2;
	food_y = rand()%(Width-5) + 2;
	canvas[food_x][food_y] = -2;
	
}


void show()           // display frame 
{
	gotoxy(0,0);                     // Move the cursor to the origin position , Clear the screen 
	int i,j;
	for (i=0;i<High;i++)
	{
		for(j=0;j<Width;j++)
		{
			if(canvas[i][j]==0)            // The unassigned , The assignment is 0 
			printf(" ");                   // Output space  
			else if(canvas[i][j]==-1)
			printf("#");                  // Output border  
			else if(canvas[i][j]==1)
			printf("@");                  // Output snakehead  
			else if(canvas[i][j]>1)
			printf("*");                  // Output snake body  
			else if(canvas[i][j]==-2)
			printf("F");                  // Export food  F 
				
		}
		printf("\n"); 
	}
	Sleep(100);
}

void updateWithoutTnput()             // User independent updates  
{
  moveSnakeByDirection();
}
void updateWithInput()               // User related updates  
{
	char input;
	if(kbhit())                      // Determine if there is input  
	{
		input=getch();               // Move according to the user's different input , Enter not required 
		if(input =='a')
		{
			moveDirection = 3;       // Position left  
			moveSnakeByDirection();
		}
		else if (input=='d')
		{
			moveDirection =4;               // Position right 
			moveSnakeByDirection();         
		}
		else if(input=='w')
		{
			moveDirection =1;              // Move the position up  
			moveSnakeByDirection();
		}
		else if (input=='s')
		{
			moveDirection =2;              // Position down  
			moveSnakeByDirection();
		 } 
	}	
}

int main()                          // The main function  
{   
    CONSOLE_CURSOR_INFO cci;
	cci.bVisible = FALSE;
	cci.dwSize = sizeof(cci);
	SetConsoleCursorInfo(GetStdHandle(STD_OUTPUT_HANDLE), &cci);

	startup();                       // call startup function  
	while(1)
	{
		show();
		updateWithoutTnput();           // User independent updates  
		updateWithInput();              // User related updates  
	}
	return 0;
 } 

notes ： When the code runs, the initialization of the snake will only show a tail , Moving to the tail of the snake will directly determine failure . The program can run , But these two problems have not been solved , It may reduce the player experience .