From 21ef4da10485ce047a90fa69bf548d358b4866b7 Mon Sep 17 00:00:00 2001
From: pfjlev589 <1600351482@qq.com>
Date: Mon, 6 Nov 2023 00:59:21 +0800
Subject: [PATCH] ADD file via upload

---
 4.txt | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 155 insertions(+)
 create mode 100644 4.txt

diff --git a/4.txt b/4.txt
new file mode 100644
index 0000000..9e29c6b
--- /dev/null
+++ b/4.txt
@@ -0,0 +1,155 @@
+#include <stdio.h>
+#include <stdbool.h>
+
+char board0[9][9] = { {'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'} };
+
+char board1[9][9] = { {'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'} };
+
+char board[9][9] = { 0 };
+
+bool dfs(char board[][9], bool row[][9], bool col[][9], bool block[][9], int i, int j)
+{
+   
+    int num ;
+    while (board[i][j] != '.')
+    {
+        if (++j >= 9)
+        {
+            i++;
+            j = 0;
+        }
+        if (i >= 9)
+        {
+            return true;
+        }
+    }
+    for (num = 0; num < 9; num++)
+    {
+        int blockIndex = i / 3 * 3 + j / 3;
+        if (!row[i][num] && !col[j][num] && !block[blockIndex][num])
+        {
+            
+            board[i][j] = (char)('1' + num);
+            row[i][num] = true;
+            col[j][num] = true;
+            block[blockIndex][num] = true;
+            if (dfs(board, row, col, block, i, j))
+            {
+                return true;
+            }
+            else
+            {
+                
+                row[i][num] = false;
+                col[j][num] = false;
+                block[blockIndex][num] = false;
+                board[i][j] = '.';
+            }
+        }
+    }
+    return false;
+}
+
+
+bool isValidSudoku(char board[][9]) {
+    bool row[9][9] = { {false} };
+    bool col[9][9] = { {false} };
+    bool block[9][9] = { {false} };
+    int i, j;
+
+    for (i = 0; i < 9; i++) {
+        for (j = 0; j < 9; j++) {
+            if (board[i][j] != '.') {
+                int num = board[i][j] - '1';
+                int blockIndex = i / 3 * 3 + j / 3;
+                if (row[i][num] || col[j][num] || block[blockIndex][num]) {
+                    printf("False:Invalid initial Sudoku matrix!\n");
+                    printf("      ");
+                    if (row[i][num]) {
+                        printf("The number %d in the row %d has been used!\n", num + 1, i + 1);
+                    }
+                    if (col[j][num]) {
+                        printf("The number %d in the col %d has been used!\n", num + 1, j + 1);
+                    }
+                    if (block[blockIndex][num]) {
+                        printf("The number %d in the block %d has been used!\n", num + 1, blockIndex + 1);
+                    }
+                    return false;
+                }
+                else {
+                    row[i][num] = true;
+                    col[j][num] = true;
+                    block[blockIndex][num] = true;
+                }
+            }
+        }
+    }
+    printf("True:Valid initial Sudoku matrix!\n");
+    return dfs(board, row, col, block, 0, 0);
+}
+
+void printMatrix(char board[][9])
+{
+    int i, j;
+    printf("      1 2 3   4 5 6   7 8 9\n");
+    printf("    +-----------------------+\n");
+    for (i = 0; i < 9; i++)
+    {
+        printf(" %d  | ", i + 1);
+        for (j = 0; j < 9; j++)
+        {
+            printf("%c ", board[i][j]);
+            if (j % 3 == 2)
+            {
+                printf("| ");
+            }
+        }
+        printf("\n");
+        if (i % 3 == 2)
+        {
+            printf("    +-----------------------+\n");
+        }
+    }
+}
+
+
+int main()
+{
+    int i, j;
+    for (i = 0; i < 9; i++)
+    {
+        for (j = 0; j < 9; j++)
+        {
+            board[i][j] = '.';
+        }
+    }
+    printf("The original Sudoku matrix:\n");
+    printMatrix(board0);
+    if (isValidSudoku(board0))
+    {
+        printf("The solution of Sudoku matrix:\n");
+        printMatrix(board0);
+    }
+    else
+    {
+        printf("No solution!");
+    }
+
+    return 0;
+}
\ No newline at end of file