diff --git a/checkMatrix.c b/checkMatrix.c
new file mode 100644
index 0000000..15c74a9
--- /dev/null
+++ b/checkMatrix.c
@@ -0,0 +1,67 @@
+#include "myMatrix.h"
+
+int checkMatrix(int matrixArr[9][9], int isPrintInfo){
+  int rowCnt[9][10]={0};
+  int colCnt[9][10]={0};
+  int bloCnt[9][10]={0};
+  for(int i=0;i<9;i++){
+    for(int j=0;j<9;j++){
+      if(matrixArr[i][j]!=0){
+        rowCnt[i][matrixArr[i][j]]++;
+        if(rowCnt[i][matrixArr[i][j]]>1){
+          if(isPrintInfo){
+            printf("\nFalse:Invalid initial Sudoku matrix!");
+            printf("\nThe number %d in the row %d has been used!",matrixArr[i][j],i+1);
+          }
+          return 0;
+        }
+        colCnt[j][matrixArr[i][j]]++;
+        if(colCnt[j][matrixArr[i][j]]>1){
+          if(isPrintInfo){
+            printf("\nFalse:Invalid initial Sudoku matrix!");
+            printf("\nThe number %d in the col %d has been used!",matrixArr[i][j],j+1);
+          }
+          return 0;
+        }
+        bloCnt[i/3*3+j/3][matrixArr[i][j]]++;
+        if(bloCnt[i/3*3+j/3][matrixArr[i][j]]>1){
+          if(isPrintInfo){
+            printf("\nFalse:Invalid initial Sudoku matrix!");
+            printf("\nThe number %d in the block %d has been used!",matrixArr[i][j],i/3*3+j/3+1);
+          }
+          return 0;
+        }
+      }
+    }
+  }
+  if(isPrintInfo){
+    printf("\nTrue:Valid initial Sudoku matrix!");
+  }
+  return 1;
+}
+
+// int main(){
+//   int board0[9][9] = {{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}};
+//   int board1[9][9] = {{8, 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}};
+
+//   printf("The original Sudoku matrix: \n");
+//   matrixOutput(board1);
+//   checkMatrix(board1,1);
+//   return 0;
+// }
\ No newline at end of file
diff --git a/fillMatrix.c b/fillMatrix.c
new file mode 100644
index 0000000..d0e973b
--- /dev/null
+++ b/fillMatrix.c
@@ -0,0 +1,44 @@
+#include "myMatrix.h"
+
+int fillMatrix(){
+  //todo
+}
+
+int main(){
+  int board0[9][9] = {{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}};
+  int board1[9][9] = {{8, 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}};
+  int board2[9][9] = {{5, 2, 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}};
+
+  printf("The original Sudoku matrix: \n");
+  matrixOutput(board1);
+  if(checkMatrix(board1,1)){
+    fillMatrix();
+  }else{
+    printf("\nNo solution!");
+  }
+  return 0;
+}
\ No newline at end of file
diff --git a/myMatrix.h b/myMatrix.h
new file mode 100644
index 0000000..e22d2c9
--- /dev/null
+++ b/myMatrix.h
@@ -0,0 +1,7 @@
+#include<stdio.h>
+#include<time.h>
+#include<stdlib.h>
+
+void matrixOutput(int matrixArr[9][9]);
+void matrixRandomInit(int matrixArr[9][9]);
+int checkMatrix(int matrixArr[9][9], int isPrintInfo);
\ No newline at end of file
diff --git a/outPut.c b/outPut.c
new file mode 100644
index 0000000..5ac757b
--- /dev/null
+++ b/outPut.c
@@ -0,0 +1,31 @@
+#include "myMatrix.h"
+
+void matrixOutput(int matrixArr[9][9])
+{
+  for (int i = 0; i < 9; i++)
+  {
+    for (int j = 0; j < 9; j++)
+    {
+      printf("%d", matrixArr[i][j]);
+      if (j != 8)
+        printf(" ");
+    }
+    if (i != 8)
+      printf("\n");
+  }
+}
+
+// int main()
+// {
+//   int board[9][9] = {{5, 3, 4, 6, 7, 8, 9, 1, 2},
+//                      {6, 7, 2, 1, 9, 5, 3, 4, 8},
+//                      {1, 9, 8, 3, 4, 2, 5, 6, 7},
+//                      {8, 5, 9, 7, 6, 1, 4, 2, 3},
+//                      {4, 2, 6, 8, 5, 3, 7, 9, 1},
+//                      {7, 1, 3, 9, 2, 4, 8, 5, 6},
+//                      {9, 6, 1, 5, 3, 7, 2, 8, 4},
+//                      {2, 8, 7, 4, 1, 9, 6, 3, 5},
+//                      {3, 4, 5, 2, 8, 6, 1, 7, 9}};
+//   matrixOutput(board);
+//   return 0;
+// }
\ No newline at end of file
diff --git a/randomInit.c b/randomInit.c
new file mode 100644
index 0000000..1f98a5a
--- /dev/null
+++ b/randomInit.c
@@ -0,0 +1,38 @@
+#include "myMatrix.h"
+
+void matrixRandomInit(int matrixArr[9][9]){
+  int map[9] = {1,2,3,4,5,6,7,8,9};
+  int mp;
+  srand(time(NULL));
+  for(int i=0;i<9;i++){
+    for(int j=0;j<9;j++){
+      matrixArr[i][j] = 0;
+    }
+  }
+  for(int i=0;i<9;i++){
+    if(i%3==0){
+      mp=0;
+      for(int j=0;j<8;j++){
+        int n = i+rand()%(8-i);
+        int tmp = map[i];
+        map[i] = map[n];
+        map[n]=tmp;
+      }
+    }
+    int k=0;
+    while(k<3){
+      int tmpP = rand()%9;
+      if(matrixArr[i][tmpP]==0){
+        matrixArr[i][tmpP] = map[mp++];
+        k++;
+      }
+    }
+  }
+}
+
+int main(){
+  int board[9][9];
+  matrixRandomInit(board);
+  matrixOutput(board);
+  return 0;
+}
\ No newline at end of file