我在Java中有一个程序,该程序检查sudoku是否有效,我有两种方法,第一个是检查所有列,子网格,行的总和,并告诉IS 45,第二个是检查所有Sudoku的总和是否为405,因此Sudoku有效,所以我正在寻找一个反面示例,在输入中我有一个有效的sudoku,但是该程序告诉是无效的,所以这是代码:
public class test_checker {
static final boolean valide=true;
static final boolean non_valide=false;
// verify every sub-grid if it is valid
static boolean check_subgrid(int a[][],int ei,int ej){
int sum=0;
for(int i=ei;i<ei+3;i++){
for(int j=ej;j<ej+3;j++){
sum=sum+a[j][i];
}
}
if(sum!=45) return non_valide;
else return valide;
}
//verify a sudoku by sum of every row & column & sub-grid
static boolean Checker1(int a[][]){
int sum=0;
//check row
for(int i=0;i<9;i++){
sum=0;
for(int j=0;j<9;j++){
sum=sum+a[i][j];
}
if(sum!=45) return non_valide;
}
//check column
for(int i=0;i<9;i++){
sum=0;
for(int j=0;j<9;j++){
sum=sum+a[j][i];
}
if(sum!=45) return non_valide;
}
//check sub-grid
for(int i=0;i<9;i=i+3){
for(int j=0;j<3;j=j+3){
if(check_subgrid(a,i,j)==non_valide) return non_valide;
}
}
return valide;
}
//verify by sum of all sudoku
static boolean Checker2(int a[][]){
int sum=0;
for(int i=0;i<9;i++){
for(int j=0;j<9;j++){
sum=sum+a[i][j];
}
}
if(sum!=405) return non_valide;
else return valide;
}
public static void main(String[] args) {
int [][] sudoku =
{
{1,2,3,4,5,6,7,8,9},
{4,5,6,7,8,9,1,2,3},
{7,8,9,1,2,3,4,5,6},
{3,1,2,9,7,8,6,4,5},
{6,4,5,3,1,2,9,7,8},
{9,7,8,6,4,5,3,1,2},
{2,3,1,5,6,4,8,9,7},
{5,6,4,8,9,7,2,3,1},
{8,9,7,2,3,1,5,6,4}
};
if(Checker1(sudoku)) System.out.println("it's valide (checker1)!");
else System.out.println("it's not valide !");
if(Checker2(sudoku)) System.out.println("it's valide (checker2) !");
else System.out.println("it's not valide !");
}
}
正如@john Bollinger所说
您应该问的是,是否有一个无效的9 x 9网格 然而,确实满足您的标准。
最简单的两种情况,我想到的是:
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5},
{5,5,5,5,5,5,5,5,5}
和您的示例,您将在哪里放置0而不是1和10而不是9。确保每个字段在行,列和子网格中都不同,并且间隔为[1,9]。
Checker2您可以将两个行的两个值转弯。在这里,我倒了第一行和第二行的4和1,显然这是无效的Sudoku,但是Checker2会给您一个积极的结果
{4,2,3,4,5,6,7,8,9},
{1,5,6,7,8,9,1,2,3},
{7,8,9,1,2,3,4,5,6},
{3,1,2,9,7,8,6,4,5},
{6,4,5,3,1,2,9,7,8},
{9,7,8,6,4,5,3,1,2},
{2,3,1,5,6,4,8,9,7},
{5,6,4,8,9,7,2,3,1},
{8,9,7,2,3,1,5,6,4}