diff --git a/任务4.c b/任务4.c
new file mode 100644
index 0000000..aeab11f
--- /dev/null
+++ b/任务4.c
@@ -0,0 +1,114 @@
+#include <stdio.h>
+#include <stdbool.h>
+
+#define SIZE 9
+void geshihua(int arr0[9][9])
+{
+    int i,j;
+    printf("|");
+    for(i=0;i<9;i++)
+    {
+        for(j=0;j<9;j++)
+        {
+            printf("%d ",arr0[i][j]);
+            
+            if(j==8)
+            {
+                printf("|\n");
+            }
+            if(i==8&&j==8)
+            break;
+            if((i+1)%3==0&&j==8&&i!=8)
+            {
+                printf("|--------------------|\n");
+            }
+            if((j+1)%3==0)
+            {
+                printf("|");
+                
+            }
+        
+        }
+    }
+}
+
+// ¼ì²éÐÐÖÐÊÇ·ñÓÐÖظ´Êý×Ö
+bool checkRow(int board[SIZE][SIZE], int row, int num) {
+	int col;
+    for (col = 0; col < SIZE; col++) {
+        if (board[row][col] == num && board[row][col] != 0) { // Ö»¼ì²é·ÇÁãÔªËØ
+            return false;
+        }
+    }
+    return true;
+}
+
+// ¼ì²éÁÐÖÐÊÇ·ñÓÐÖظ´Êý×Ö
+bool checkColumn(int board[SIZE][SIZE], int col, int num) {
+	int row;
+    for (row = 0; row < SIZE; row++) {
+        if (board[row][col] == num && board[row][col] != 0) { // Ö»¼ì²é·ÇÁãÔªËØ
+            return false;
+        }
+    }
+    return true;
+}
+
+// ¼ì²é3x3×Ó¾ØÕóÖÐÊÇ·ñÓÐÖظ´Êý×Ö
+bool checkBox(int board[SIZE][SIZE], int rowStart, int colStart, int num) {
+	int row,col;
+    for (row = 0; row < 3; row++) {
+        for (col = 0; col < 3; col++) {
+            if (board[row + rowStart][col + colStart] == num && board[row + rowStart][col + colStart] != 0) { // Ö»¼ì²é·ÇÁãÔªËØ
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
+// ¼ì²é³õʼÊý¶À¾ØÕóÊÇ·ñÓÐЧ
+bool isValidInitialSudoku(int board[SIZE][SIZE]) {
+	int row,col;
+    for (row = 0; row < SIZE; row++) {
+        for (col = 0; col < SIZE; col++) {
+            if (board[row][col] != 0) { // Ö»¼ì²é·ÇÁãÔªËØ
+                int num = board[row][col];
+                if (!checkRow(board, row, num) || !checkColumn(board, col, num) || !checkBox(board, row - row % 3, col - col % 3, num)) {
+                    // Êä³ö²»Âú×ãµÄÔ­Òò
+                    if (!checkRow(board, row, num)) {
+                        printf("False:Invalid initial Sudoku matrix! The number %d in the row %d has been used!\n", num, row + 1);
+                    } else if (!checkColumn(board, col, num)) {
+                        printf("False:Invalid initial Sudoku matrix! The number %d in the column %d has been used!\n", num, col + 1);
+                    } else {
+                        printf("False:Invalid initial Sudoku matrix! The number %d in the block %d has been used!\n", num, (row / 3) * 3 + 1); // ¼ò»¯Êä³ö£¬Ö»±íʾÊÇÄĸö3x3¿é£¬²»¾«È·µ½ÁÐ
+                    }
+                    return false;
+                }
+            }
+        }
+    }
+    printf("True:Valid initial Sudoku matrix!\n");
+    return true;
+}
+
+int main() {
+    printf("¡°The original Sudoku matrix:\n");
+    int board[SIZE][SIZE] = {
+        // ÕâÀïÌîÈëÄãµÄ²Ðȱ¾ØÕó£¬0±íʾ¿Õȱ²¿·Ö£¬·ÇÁãÊý×Ö±íʾÒѸø³öµÄÊý×Ö
+        {5, 3, 0, 0, 7, 0, 0, 0, 0},
+        {6, 0, 0, 1, 9, 5, 0, 0, 0},
+        {0, 9, 8, 0, 0, 0, 0, 6, 0},
+        {8, 0, 0, 0, 6, 0, 0, 0, 3},
+        {4, 0, 0, 8, 0, 3, 0, 0, 1},
+        {7, 0, 0, 0, 2, 0, 0, 0, 6},
+        {0, 6, 0, 0, 0, 0, 2, 8, 0},
+        {0, 0, 0, 4, 1, 9, 0, 0, 5},
+        {0, 0, 0, 0, 8, 0, 0, 7, 9}
+    };
+    geshihua(board);
+
+    isValidInitialSudoku(board);
+
+    return 0;
+}