此题方法多种,我用规范的DFS来求解
题目:方格填数
如下的10个格子,填入0~9的数字。要求:连续的两个数字不能相邻。 
(左右、上下、对角都算相邻)一共有多少种可能的填数方案? 
DFS(深度优先搜索遍历求合格条件总数)--07--DFS--蓝桥杯方格填数-LMLPHP 

输出

请填写表示方案数目的整数。 
 #include <iostream>
#include <vector>
#include <stdio.h>
#include <queue>
#include <cmath>
using namespace std;
const int ROW = ;
const int COL = ; int my[] = {};
int sum = ;
int num = ; int dd8[][] = {{-,},{,},{,},{,-},{-,},{,},{-,-},{,-}};
int dd[][] = {{-,},{,},{,},{,-}};
vector<vector<int> >sig[];
vector<vector<int> >matrix(ROW,vector<int>(COL,-)); bool check(int i,int j,int number){
if(my[number] == )
return false;
for(int zz = ;zz < ;zz++){
int ii = i + dd8[zz][];
int jj = j + dd8[zz][];
if(ii < ||jj < ||ii >= ROW||jj >= COL)
continue;
if(ii == &&jj ==)
continue;
if(ii == ROW - &&jj == COL - )
continue;
if(abs(matrix[ii][jj] - number) == )
return false;
}
return true;
}
void rightload(){
sig[sum] = matrix;
}
int checkrightload(){
for(int k = ;k < sum;k++){
if(sig[k] == matrix)
return ;
}
return ;
}
void lock(int i,int j,int k){
num--;
my[k] = ;
matrix[i][j] = k;
}
void unlock(int i,int j,int k){
num++;
my[k] = ;
matrix[i][j] = -;
}
void dfs(int i,int j){
for(int zz = ;zz < ;zz++){
int ii = i + dd[zz][];
int jj = j + dd[zz][];
if(ii < ||jj < ||ii >= ROW||jj >= COL)
continue;
if(ii == &&jj ==)
continue;
if(ii == ROW - &&jj == COL - )
continue;
if(matrix[ii][jj] == -){
for(int k = ;k < ;k++){
if(check(ii,jj,k) == true){
lock(ii,jj,k);
if(num == ){
if(checkrightload() == ){
rightload();
sum++;
}
unlock(ii,jj,k);
return;
}
else
dfs(ii,jj);
unlock(ii,jj,k); }
}
}
}
}
int main(){
for(int i = ;i < ;i++){
lock(,,i);
dfs(,);
unlock(,,i);
}
cout << sum <<endl;
return ;
}
05-11 20:26