C language to achieve three chess game (detailed explanation)

One . Introduction to Sanzi chess game

I believe everyone has played sanziqi , Here is a brief introduction !
It's a kind of black and white chess . Sanzi chess is a traditional folk game , Also called Jiugong chess 、 Circle fork 、 A dragon 、 Tic tac toe chess, etc . Just walk your three pieces into a line , He won

Two . Description of the game implementation process

1. Print menu , Prompt the player to make a choice , ad locum , What we set up is ：
   choice 1, Play a game
   choice 0, Quit the game
   Select another number , Prompt input error , Let the user re-enter

2. Print chessboard

3. Players play chess

4. The computer plays chess

5. Judgement of winning or losing

3、 ... and .C Language code implementation

1. Overview of the overall framework and code display

Finally realize the complete code of the game , We In three files , It is convenient to manage our code .

The three documents are ：
(1)test.c
For testing game logic
(2)game.h
Function declaration related to game implementation , Symbol declaration , The header file contains
(3)game.c
The realization of game related functions

Then we will show all the codes in the three documents for your reference , Then I will explain it in detail ：
(1)test.c

#include "game.h"
void menu()
{
    
	printf("**********************************\n");
	printf("****** 1. play *******\n");
	printf("****** 0. exit *******\n");
	printf("**********************************\n");
}
void play_game()
{
    
	char ret = '0';
	char board[ROW][COL] = {
     0 };
	init_board(board, ROW, COL);// Initialize array 
	print_board(board, ROW, COL);// Print chessboard 
	while (1)
	{
    
		player_move(board, ROW, COL);// Players play chess 
		print_board(board, ROW, COL);// Print chessboard 
		// Judgement of winning or losing 
		ret = is_win(board, ROW, COL);
		if (ret != 'C')
			break;
		computer_move(board, ROW, COL);// The computer plays chess 
		print_board(board, ROW, COL);// Print chessboard 
		// Judgement of winning or losing 
		ret = is_win(board, ROW, COL);
		if (ret != 'C')
			break;
	}
	if (ret == '*')
		printf(" You win \n");
	else if (ret == '#')
		printf(" Computers win \n");
	else if (ret == 'Q')
		printf(" It ends in a draw \n");

}

int main()
{
    
	srand((unsigned int)time(NULL));// Set random number generator 
	int elect = 0;
	do
	{
    
		menu();
		printf(" Please select ：");
		scanf("%d", &elect);
		switch (elect)
		{
    
		case 1:
			play_game();
			break;
		case 0:
			printf(" Quit the game !!!\n");
			break;
		default:
			printf(" Wrong choice , Please reselect !!!\n");
			break;
		}
	} while (elect);
	return 0;
}

(2)game.h

#define _CRT_SECURE_NO_WARNINGS
#define ROW 3 //ROW—— That's ok 
#define COL 3 //COL—— Column 

#include <stdio.h>
#include <stdlib.h>//srand The required header file 
#include <time.h>//time The header file required by the function 


// Function declaration 
void init_board(char board[ROW][COL], int row, int col);// Initialize array 

void print_board(char board[ROW][COL], int row, int col);// Print chessboard 

void player_move(char board[ROW][COL], int row, int col);// Players play chess 

void computer_move(char board[ROW][COL], int row, int col);// The computer plays chess 

char is_win(char board[ROW][COL], int row, int col);// Judgement of winning or losing 

(3)game.c

#include "game.h"

// Initialize array 
void init_board(char board[ROW][COL], int row, int col)
{
    
	int i = 0;
	int j = 0;
	for (i = 0; i < row; i++)
	{
    
		for (j = 0; j < col; j++)
		{
    
			board[i][j] = ' ';
		}
	}
}


// Print chessboard 
void print_board(char board[ROW][COL], int row, int col)
{
    
	int i = 0;
	for (i = 0; i < row; i++)
	{
    
		// Print " | | "
		int j = 0;
		for (j = 0; j < col; j++)
		{
    
			printf(" %c ", board[i][j]);
			if (j < col - 1)
				printf("|");
		}
		printf("\n");
		// Print ---|---|---, Notice that the last line does not 
		if (i < row - 1)
		{
    
			for (j = 0; j < col; j++)
			{
    
				printf("---");
				if (j < col - 1)
					printf("|");
			}
			printf("\n");
		}
	}
}


// Players play chess 
void player_move(char board[ROW][COL], int row, int col)
{
    
	printf(" Players play chess ：\n");
	int x = 0;
	int y = 0;
	while (1)
	{
    
		printf(" Please enter the coordinates to play chess ：");
		scanf("%d %d", &x, &y);
		if (x >= 1 && x <= row && y >= 1 && y <= col)
		{
    
			if (board[x - 1][y - 1] == ' ')
			{
    
				board[x - 1][y - 1] = '*';
				break;
			}
			else
				printf(" This coordinate is already occupied , Please re-enter ：\n");
		}
		else
			printf(" Illegal coordinates , Re input \n");
	}
}


// The computer plays chess 
void computer_move(char board[ROW][COL], int row, int col)
{
    
	printf(" The computer plays chess ：\n");
	while (1)
	{
    
		int x = rand() % row;//rand The range of random numbers generated by the function is relatively large, so we give it % On 3
		int y = rand() % col;// The range is exactly 0---2
		if (board[x][y] == ' ')
		{
    
			board[x][y] = '#';
			break;
		}
	}
}

// If the chessboard is full , return 1, Dissatisfaction returns 0;
static int is_full(char board[ROW][COL], int row, int col)
{
    
	int i = 0;
	for (i = 0; i < row; i++)
	{
    
		int j = 0;
		for (j = 0; j < col; j++)
		{
    
			if (' ' == board[i][j])
				return 0;
		}
	}
	return 1;
}


// Judgement of winning or losing 
char is_win(char board[ROW][COL], int row, int col)
{
    
	// Judge that the rows are equal 
	int i = 0;
	for (i = 0; i < row; i++)
	{
    
		if (board[i][0] == board[i][1] && board[i][1] == board[i][2] && board[i][0] != ' ')
		{
    
			return board[i][0];
		}
	}

	// Judge whether the columns are equal 
	for (i = 0; i < col; i++)
	{
    
		if (board[0][i] == board[1][i] && board[1][i] == board[2][i] && board[0][i] != ' ')
		{
    
			return board[0][i];
		}
	}
	
	// Judge the main diagonal 
	if (board[0][0] == board[1][1] && board[1][1] == board[2][2] && board[1][1] != ' ')
	{
    
		return board[1][1];
	}

	// Judge the sub diagonal 
	if (board[0][2] == board[1][1] && board[1][1] == board[2][0] && board[1][1] != ' ')
	{
    
		return board[1][1];
	}

	// Judge a draw 
	if (is_full(board, row, col) == 1)
	{
    
		return 'Q';
	}

	// Keep playing 
	return 'C';
}

2. Implementation test of the overall logic of the game

We first in test.c The document implements the overall process of the Sanzi game , Test whether the logic is correct ：

#include <stdio.h>

void menu()
{
    
	printf("**********************************\n");
	printf("****** 1. play *******\n");
	printf("****** 0. exit *******\n");
	printf("**********************************\n");
}
void play_game()
{
    
	printf(" Play a game \n");
}

int main()
{
    
	int elect = 0;
	do
	{
    
		menu();
		printf(" Please select ：");
		scanf("%d", &elect);
		switch (elect)
		{
    
		case 1:
			play_game();
			break;
		case 0:
			printf(" Quit the game !!!\n");
			break;
		default:
			printf(" Wrong choice , Please reselect !!!\n");
			break;
		}
	} while (elect);
	return 0;
}

Here we will not implement the functions of the game , Replace with a sentence , Because now I'm just testing the logic ：

Take a look at the results ：

Logical correctness , Next, implement each function step by step .

3. The specific process of the game is realized

（1） Print chessboard

Let's see what the chessboard looks like first ：

Look at the , Can we Use a two-dimensional array to simulate the chessboard , Each element is initialized as a space ‘ ’, But we see that , There are separation lines between each chessboard , So we have to print the separation line .
to glance at Finally, the chessboard of our code printing ：

The size of the general chessboard 3X3 Of , however , If one day we feel 3X3 Your chessboard is too small , Playing is not enjoyable , Want to change the size of the chessboard , What shall I do? , Is it right to put all 3 They are all changed into 5 Well , in order to It is convenient to change the size of the chessboard , Let's just put it in the header file game.h of use #define Define an identifier constant , such , It will be convenient to modify the size of the chessboard in the future .
stay The header file game.h in ：

#define ROW 3 //ROW—— That's ok 
#define COL 3 //COL—— Column 

Of course, we want to be in test.c or game.c Used in , You need to include the header change file , But notice , contain Header file defined by ourselves , Need to use ” “ instead of < >：

I want to change the size of the chessboard in the future , Just modify these two numbers .

Since we want to use a two-dimensional array , First of all, we need to Define a 3X3 And then pass it as a parameter ：

Implement the initialization array function init_board():

Next we're going to Realize the function of printing chessboard print_board()：

Look at the effect ：

We use multi file management , Remember to The function declaration is placed in game.h in

function print_board(),init_board（） Put the implementation in game.c in .

（2） Design a function to realize that players play chess

First of all, let's stipulate , The player's pieces use ” * “ Express , The computer's chess pieces are used ” # “ Express .
How can players play chess , We let The player enters a coordinate , Then put a chess piece on this coordinate .
If you use coordinates , We have to consider several issues ：

1. Whether the coordinates entered by the player are out of bounds ？
2. The player outputs whether the coordinates have been used ？
3. For players , He may not know that the subscript of the array is from 0 At the beginning , So player input （1,1）, We need to help him put it into the array subscript （0,0） In the right place .
resolvent ：
When coordinate , Cross the border or have been occupied , Let the user re-enter ;
Coordinates entered by the user （x,y), Subtract both numbers 1 That's it
Implementation function ：

Of course , Don't forget to game.h Make a statement in .
See the effect ：

Okay , The player's task of playing chess is completed .

（3） Design functions to achieve computer chess

How to let the computer play chess ？
We can use rand Function generates two random numbers , Indicates the coordinates of the computer to play chess , If the coordinates are right , Put one in this position ” # “.
Pay attention to rand The function needs to call before generating random numbers srand Set up a random number generator , About rand You can go down to learn about the detailed usage of function .
Design function ：

Let's see the effect ：

Okay , The computer chess function is completed .

（4） Design a function to judge whether you win or lose

To judge whether you win or lose , We can stipulate this , If A function of winning or losing is——win
return “ * ”, Then the player wins ,
return “ # ”, Computers win ,
return “ C ”, The game goes on ;
return “ Q ”, It ends in a draw .

// Judgement of winning or losing 
char is_win(char board[ROW][COL], int row, int col)
{
    
	// Judge that the rows are equal 
	int i = 0;
	for (i = 0; i < row; i++)
	{
    
		if (board[i][0] == board[i][1] && board[i][1] == board[i][2] && board[i][0] != ' ')
		{
    
			return board[i][0];
		}
	}

	// Judge whether the columns are equal 
	for (i = 0; i < col; i++)
	{
    
		if (board[0][i] == board[1][i] && board[1][i] == board[2][i] && board[0][i] != ' ')
		{
    
			return board[0][i];
		}
	}
	
	// Judge the main diagonal 
	if (board[0][0] == board[1][1] && board[1][1] == board[2][2] && board[1][1] != ' ')
	{
    
		return board[1][1];
	}

	// Judge the sub diagonal 
	if (board[0][2] == board[1][1] && board[1][1] == board[2][0] && board[1][1] != ' ')
	{
    
		return board[1][1];
	}

	// Judge a draw 
	if (is_full(board, row, col) == 1)
	{
    
		return 'Q';
	}

	// Keep playing 
	return 'C';
}

Here we use another function to judge whether the chessboard is full ：

// If the chessboard is full , return 1, Dissatisfaction returns 0;
static int is_full(char board[ROW][COL], int row, int col)
{
    
	int i = 0;
	for (i = 0; i < row; i++)
	{
    
		int j = 0;
		for (j = 0; j < col; j++)
		{
    
			if (' ' == board[i][j])
				return 0;
		}
	}
	return 1;
}

Come here , All the functions are finished , Let's play ：

Of course, there are still many improvements in this code , If you are interested, you can try it yourself ！！！
If there's something wrong with it , Welcome to correct ！！！