Shtirlits - SGU 125（搜索）

#include<stdio.h>
#include<algorithm>
#include<string.h>
#include<math.h>
using namespace std;

const int MAXN = 10;

int dir[4][10][5] = {{},{},{{},{2,3},{1,4},{1,4},{2,3}},
{{},{2,4},{1,3,5},{2,6},{1,5,7},{2,4,6,8},{3,5,9},{4,8},{5,7,9},{6,8}}};
int near[4][10][5] = {{},{},{{},{},{1},{1},{2,3}},{{},{},{1},{2},{1},{2,4},{3,5},{4},{5,7},{6,8}}};
int B[MAXN], A[MAXN], ok, N;

bool nBigger(int k)
{
int i, cnt = 0, zero=0;

for(i=0; dir
[k][i]; i++)
{
if(A[k] < A[dir
[k][i]])
cnt++;
if(!A[dir
[k][i]])
zero++;
}

if(cnt > B[k])
return false;
if(cnt+zero < B[k])
return false;
return true;
}
void DFS(int k)
{
int i, j;

if(k == N*N+1)
ok = 1;

if(ok)return ;

for(i=1; i<MAXN; i++)
{
A[k] = i;
if(nBigger(k) == false)
continue;
for(j=0; near
[k][j]; j++)
{
if(!nBigger(near
[k][j]))
break;
}

if(near
[k][j] == 0)
DFS(k+1);

if(ok)return ;
}

A[k] = 0;
}

int main()
{
scanf("%d", &N);

for(int i=1; i<=N; i++)
for(int j=1; j<=N; j++)
scanf("%d", &B[(i-1)*N+j]);

DFS(1);

if(!ok)
printf("NO SOLUTION\n");
else
{
for(int i=1; i<=N; i++)
for(int j=1; j<=N; j++)
printf("%d%c", A[(i-1)*N+j], j==N?'\n':' ');
}

return 0;
}