學渣帶你刷Leetcode0036有效的數獨

題目描述

判斷一個 9x9 的數獨是否有效。只需要根據以下規則，驗證已經填入的數字是否有效即可。

數字 1-9 在每一行只能出現一次。
數字 1-9 在每一列只能出現一次。
數字 1-9 在每一個以粗實線分隔的 3x3 宮內只能出現一次。

上圖是一個部分填充的有效的數獨。

數獨部分空格內已填入了數字，空白格用 '.' 表示。

示例 1:

輸入:
[
  ["5","3",".",".","7",".",".",".","."],
  ["6",".",".","1","9","5",".",".","."],
  [".","9","8",".",".",".",".","6","."],
  ["8",".",".",".","6",".",".",".","3"],
  ["4",".",".","8",".","3",".",".","1"],
  ["7",".",".",".","2",".",".",".","6"],
  [".","6",".",".",".",".","2","8","."],
  [".",".",".","4","1","9",".",".","5"],
  [".",".",".",".","8",".",".","7","9"]
]
輸出: true
示例 2:

輸入:
[
  ["8","3",".",".","7",".",".",".","."],
  ["6",".",".","1","9","5",".",".","."],
  [".","9","8",".",".",".",".","6","."],
  ["8",".",".",".","6",".",".",".","3"],
  ["4",".",".","8",".","3",".",".","1"],
  ["7",".",".",".","2",".",".",".","6"],
  [".","6",".",".",".",".","2","8","."],
  [".",".",".","4","1","9",".",".","5"],
  [".",".",".",".","8",".",".","7","9"]
]
輸出: false
解釋: 除了第一行的第一個數字從 5 改爲 8 以外，空格內其他數字均與 示例1 相同。
     但由於位於左上角的 3x3 宮內有兩個 8 存在, 因此這個數獨是無效的。
說明:

一個有效的數獨（部分已被填充）不一定是可解的。
只需要根據以上規則，驗證已經填入的數字是否有效即可。
給定數獨序列只包含數字 1-9 和字符 '.' 。
給定數獨永遠是 9x9 形式的。

來源：力扣（LeetCode）
鏈接：https://leetcode-cn.com/problems/valid-sudoku
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白話題目：

[suˈdəʊkuː],判斷已經填入的狀態是否有效。就是同行同列，同九宮格不能有重複的1，2，3,4,5,6,7,8,9。

算法：

（1）輸入測試，就是從一個txt文檔中讀入輸入  用到了fopen，fgets，strtok（用空格分隔字符串）

（2）存入char **board中，注意不能用board[][],當初寫的時候出現了問題

（3）判斷

//1，循環判斷行是否都有效
//2，循環判斷列是否都有效
//3，循環判斷每個9宮格是否都有效
//三者都有效時整個數獨纔有效

思路簡單，容易理解，完成的就是代碼實現的事，至於後面的37題，我們再想辦法。

今朝有酒今朝醉，明日愁來明日愁。

詳細解釋關注 B站  【C語言全代碼】學渣帶你刷Leetcode 不走丟 https://www.bilibili.com/video/BV1C7411y7gB

C語言完全代碼

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#define BUF_SIZE (200)
bool isValidLine(char** board, int line)
{
    int iNumFlag[9]= {0};
    int index= 0;
    bool bRet= true;

    for (index = 0; index < 9; index++)
    {
        if ((board[line][index] >= '1') && (board[line][index] <= '9'))
        {
            if (1 == iNumFlag[board[line][index] - '1'])
            {
                bRet = false;
                return bRet;
            }
            else
            {
                iNumFlag[board[line][index] - '1'] = 1;
            }
        }
    }
    return bRet;
}

bool isValidColumn(char** board, int column)
{
    int     iNumFlag[9]     = {0};
    int     index           = 0;
    bool    bRet            = true;

    for (index = 0; index < 9; index++)
    {
        if ((board[index][column] >= '1') && (board[index][column] <= '9'))
        {
            if (1 == iNumFlag[board[index][column] - '1'])
            {
                bRet = false;
                return bRet;
            }
            else
            {
                iNumFlag[board[index][column] - '1'] = 1;
            }
        }
    }
    return bRet;
}

bool isvalidSpace(char** board, int line, int column)
{

    int     iNumFlag[9]     = {0};
    int     i               = 0;
    int     j               = 0;
    bool    bRet            = true;

    for (i = 0; i < 3; i++)
    {
        for (j = 0; j < 3; j++)
        {
            if ((board[line + i][column + j] >= '1') && (board[line + i][column + j] <= '9'))
            {
                if (1 == iNumFlag[board[line + i][column + j] - '1'])
                {
                    bRet = false;
                    return bRet;
                }
                else
                {
                    iNumFlag[board[line + i][column + j] - '1'] = 1;
                }
            }
        }
    }
    return bRet;
}

bool isValidSudoku(char** board, int boardSize, int* boardColSize)
{
    int     i       = 0;
    int     j       = 0;
    bool    bRet    = true;
    printf("start\n");
    //行判斷
    for (i = 0; i < 9; i++)
    {
        if (false == isValidLine(board, i))
        {
            bRet = false;
            return bRet;
        }
    }

    //列判斷
    for (j = 0; j < 9; j++)
    {
        if (false == isValidColumn(board, j))
        {
            bRet = false;
            return bRet;
        }
    }

    //9宮格判斷
    for (i = 0; i < 9; i += 3)
    {
        for (j = 0; j < 9; j += 3)
        {
            if (false == isvalidSpace(board, i, j))
            {
                bRet = false;
                return bRet;
            }
        }
    }
    return bRet;
}


int main()
{
    int boardSize=9;
    int boardColSize=9;

    char** board=(char**)malloc(sizeof(char*)*boardSize);


    char arr[9][BUF_SIZE]= {0};
    FILE *fp=fopen("suduku.txt","r");
    if(!fp)
    {
        printf("open fail\n");
    }
    int i=0;
    int j=0;
    char buf[BUF_SIZE]= {'0'};
    while((fgets(arr[i],BUF_SIZE,fp))!=NULL)
    {
        puts(arr[i]);   //每一行都被存在了arr[i]中
        board[i]=(char*)malloc(sizeof(char)*boardColSize);
        char *subarr= strtok(arr[i]," ");
        int  j=0;
        while(subarr!=NULL)
        {
            // printf( "---%d\n", strlen(subarr));
            //  printf( "---%s\n", subarr );
            board[i][j]=subarr[0];  //拆分的是字符串，  回車也有，我們就取一個第一位就好了
            subarr =strtok(NULL," ");//繼續
            j++;
        }
        i++;
    }
    printf("\n");
    fclose(fp);
    for(i=0; i<boardSize; i++)
    {
        for(j=0; j<boardColSize; j++)
        {
            printf("%c",board[i][j]);
        }
        printf("\n");
    }

    bool result=isValidSudoku(board, boardSize,&boardColSize);
    printf("%d\n", result);

    return 0;
}