#創建三個檔案：1 game.h頭檔案-用于宣告函式，2 game.c源檔案-用于實作自定義函式，3 Sanziqi.c源檔案-用于總體三子棋游戲框架，

##1-總體三子棋框架實作

int main()
{
	int input = 0;
	srand((unsigned int)time(NULL));
	do
	{
		menu();
		printf("請選擇：");
		scanf("%d", &input);
		switch (input)
		{
		case 1:
			printf("三子棋\n");
			game();
			break;
		case 0:
			printf("退出游戲\n");
			break;
		default:
			printf("選擇錯誤\n");
			break;
		}
	} while (input);
	return 0;
}

##2-總體完成后 實作里面menu（）函式和game（）函式

void menu()
{
	printf("****************************\n");
	printf("***********1-paly***********\n");
	printf("***********0-exit***********\n");
	printf("****************************\n");
}

void game()
{
	char board[ROW][COL];//創建棋盤
	InitBoard(board, ROW, COL);//初識話棋盤
	DisplayBoard(board, ROW, COL);//列印棋盤
	int ret = 0;
	while (1)
	{
		PlayerMove(board, ROW, COL);//玩家移動
		DisplayBoard(board, ROW, COL);
		ret=IsWin(board, ROW, COL);//判斷輸贏
		if(ret!='C')
		{
			break;
		}
		ComputerMove(board, ROW, COL);//電腦移動
		DisplayBoard(board, ROW, COL);
		ret = IsWin(board, ROW, COL);//判斷輸贏
		if (ret != 'C')
		{
			break;
		}
		
	}
	if (ret == '*')
	{
		printf("玩家贏！\n");
	}
	else if(ret == '#')
	{
		printf("電腦贏！\n");
	}
	else
	{
	printf("平局！\n");
    }
	DisplayBoard(board, ROW, COL);
}

##3-將game（）里函式在game.h檔案里做宣告

##4- 在game.c檔案里實作函式

#include"game.h"

void InitBoard(char board[ROW][COL], int row, int col)//初始化棋盤
{
	int i = 0;
	for (i = 0; i < row; i++)
	{
		int j = 0;
		for (j = 0; j < col; j++)
		{
			board[i][j] = ' ';
		}
	}
}

void DisplayBoard(char board[ROW][COL], int row, int col)//列印棋盤
{
	/*int i = 0;
	for (i = 0; i < row; i++)
	{
		int j = 0;
		for (j = 0; j < col; j++)
		{
			printf("%c", board[i][j]);
		}
		printf("\n");
	}*/


	/*int i = 0;
	for (i = 0; i < row; i ++)
	{
		printf(" %c | %c | %c | \n", board[i][0], board[i][1], board[i][0]);
		if(i<row-1)
		printf("---|---|---\n");
	}*/

//上述代碼無法同時實作行列同時增大或者減小

	int i = 0;
	for (i = 0; i < row; i++)
	{
		int j = 0;
		for (j = 0; j < col; j++)
		{
			printf(" %c ", board[i][j]);
			if (j < col - 1)
				printf("|");
		}
		printf("\n");
		if (i < row - 1)
		{
			for (j = 0; j < col; j++)
			{
				printf("---");
				if (j < col - 1)
					printf("|");
			}
		}
		printf("\n");
	}

}

void PlayerMove(char board[ROW][COL], int row, int col)//玩家下棋
{
	printf("玩家走：\n");
	int x = 0;
	int y = 0;
	while (1)
	{
		printf("請輸入坐標：");
		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("坐標被占用，請重新輸入！\n");
			}
		}
		else
		{
			printf("坐標超出范圍！\n");
		}
	}
}

void ComputerMove(char board[ROW][COL], int row, int col)//電腦下棋
{
	int x = 0;
	int y = 0;
	system("cls");
	printf("電腦走！\n");
	while (1) 
	{
		x = rand() % row;//隨機值
		y = rand() % col;//隨機值
		if (board[x][y] == ' ')//電腦隨機落子標記為'#'
		{
			board[x][y] = '#';
			break;
		}
	}

}

int Is_full(char board[ROW][COL], int row, int col)//判斷棋盤落子是否滿了
{
	int i = 0;
	int j = 0;
	for (i = 0; i < row; i++)
	{
		for (j = 0; j < col; j++)//遍歷i j達到查看整個棋盤個目的
		{
			if (board[i][j] == ' ')
			{
				return 0;
			}
		}
	}
	return 1;
}

char IsWin(char board[ROW][COL], int row, int col)//判斷游戲勝利條件
{
	int i = 0;
	for (i = 0; i < row; i++)//一行是否為同一棋子
	{
		if (board[i][0] == board[i][1] && board[i][1] == board[i][2] && board[i][0] != ' ')
		{
			return board[i][1];
		}
	}
	for (i = 0; i < col; i++)//一列是否為同一棋子
	{
		if (board[0][i] == board[1][i] && board[1][i] == board[2][i] && board[0][i] != ' ')
		{
			return board[1][i];
		}
	}
		if (board[0][0] == board[1][1] && board[1][1] == board[2][2] && board[1][1] != ' ')
			return board[1][1];
		if (board[0][2] == board[1][1] && board[1][1] == board[2][0] && board[1][1] != ' ')
			return board[1][1];//兩個斜對角

		if (Is_full(board, row, col))
		{
			return 'Q';
		}
		else
			return 'C';
	
}

#總結：三子棋是對一個二維陣列的內容修改和判斷，使用到了函式，回圈，判斷，預處理指令，二維陣列，