在用C语言解决数独问题的时候,试图使用一个void operation函数把sudoku[9][9] 9 * 9的数独作为参数并且在操作后直接改变sudoku数组内的数据,但是最终只能实现在函数内部改变,却不能在其他函数(如:main函数,或者其他调用operation的函数)的中调用operation达到改变sudoku数组的结果。
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
void print_sudoku(int sudoku[9][9])
{
printf("The Sudoku contains:\n");
for (int j=0; j<9; j++)
{
for (int i=0; i<9;i++)
{
printf("%d ",sudoku[j][i]);
}
printf("\n");
}
}
int rowclmrepeat(int sudoku[9][9], int row, int column, int num){//if repeat return 0, else(valid) return 1
for(int i = 0; i < 9; i ++){
if(sudoku[i][column] == num){
return 0;
}
}
for(int i = 0; i < 9; i++){
if(sudoku[row][i] == num){
return 0;
}
}
return 1;
}
int chunkrepeat(int sudoku[9][9], int row, int column, int num){//if repeat return 0; else(valid) return 1
int rstart, clstart;
rstart = (row/3)*3;
clstart = (column/3)*3;
for(int i = rstart; i < rstart + 3; i++){
for(int j = clstart; j < clstart + 3; j++){
if(row != i && column != j && sudoku[i][j] == num){
return 0;
}
}
}
return 1;
}
void operate(int sudoku[9][9], int row, int column){
if(row > 8){//递归完毕,打印结果
printf("\n");
for(int a = 0; a < 9; a++){
for(int b = 0; b < 9; b ++){
printf("%d ", sudoku[a][b]);
}
printf("\n");
}
return;
}
if(sudoku[row][column] == 0){
for(int i = 1; i < 10; i++){
if(rowclmrepeat(sudoku, row, column, i) == 1 && chunkrepeat(sudoku, row, column, i) == 1){
int *p;
p = &(sudoku[row][column]);
*p = i;
operate(sudoku, row + (column + 1)/9, (column + 1)%9);
}
int *p;
p = &(sudoku[row][column]);
*p = i;
sudoku[row][column] = 0;
}
}
else{
operate(sudoku, row + (column + 1)/9, (column + 1)%9);
}
}
void solve_sudoku(int sudoku[9][9], int depth){
operate(sudoku, 0, 0);
}
int main(){
int Sudoku[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}};
printf("Input puzzle is:\n");
print_sudoku(Sudoku);
solve_sudoku(Sudoku, 1);
printf("Solution is:\n");
print_sudoku(Sudoku);
return 0;
}
Input puzzle is:
The Sudoku contains:
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
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
Solution is:
The Sudoku contains:
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
Input puzzle is:
The Sudoku contains:
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
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
Solution is:
The Sudoku contains:
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
不应该啊,函数参数二维数组可以修改数组内容啊。
估计递归有点问题,在进入到row > 8时结果是正确的,可能在递归回退时又修改回去了,导致最终数组没有变化