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DLX 900MS过了
#include<cstring>
#include<cstdio>
#include<map>
using namespace std;
struct DLX{
const static int maxn=7500;
#define FF(i,A,s) for(int i = A[s];i != s;i = A[i])
int L[maxn],R[maxn],U[maxn],D[maxn];
int size,col[maxn],row[maxn],s[maxn],H[900];
bool vis[900];
int ans[maxn],cnt;
void init(int m){
for(int i=0;i<=m;i++){
L[i]=i-1;R[i]=i+1;U[i]=D[i]=i;s[i]=0;
}
memset(H,-1,sizeof(H));
L[0]=m;R[m]=0;size=m+1;
}
void link(int r,int c){
U[size]=c;D[size]=D[c];U[D[c]]=size;D[c]=size;
if(H[r]<0)H[r]=L[size]=R[size]=size;
else {
L[size]=H[r];R[size]=R[H[r]];
L[R[H[r]]]=size;R[H[r]]=size;
}
s[c]++;col[size]=c;row[size]=r;size++;
}
void del(int c){//精确覆盖
L[R[c]]=L[c];R[L[c]]=R[c];
FF(i,D,c)FF(j,R,i)U[D[j]]=U[j],D[U[j]]=D[j],--s[col[j]];
}
void add(int c){ //精确覆盖
R[L[c]]=L[R[c]]=c;
FF(i,U,c)FF(j,L,i)++s[col[U[D[j]]=D[U[j]]=j]];
}
bool dfs(int k){//精确覆盖
if(!R[0]){
cnt=k;return 1;
}
int c=R[0];FF(i,R,0)if(s[c]>s[i])c=i;
del(c);
FF(i,D,c){
FF(j,R,i)del(col[j]);
ans[k]=row[i];if(dfs(k+1))return true;
FF(j,L,i)add(col[j]);
}
add(c);
return 0;
}
}dlx;
const int maxn=(int)1e3;
char s[maxn];
int calg(int x,int y)
{
if(x<4)
{
if(y<4)
return 1;
else if(y<7)
return 2;
else
return 3;
}
else if(x<7)
{
if(y<4)
return 4;
else if(y<7)
return 5;
else
return 6;
}
else
{
if(y<4)
return 7;
else if(y<7)
return 8;
else
return 9;
}
}
void addedge(int line,int x,int y,int now)
{
dlx.link(line,(x-1)*9+y);
dlx.link(line,81+(x-1)*9+now);
dlx.link(line,162+(y-1)*9+now);
dlx.link(line,243+(calg(x,y)-1)*9+now);
}
int a[100][100];
struct node
{
int x;
int y;
int now;
};
int main()
{
while(scanf("%s",s)!=EOF)
{
if(s[0]=='e')
{
return 0;
}
dlx.init(81*4);
int cnt=0;
int line=1;
map<int,node>mp;
for(int i=1;i<=9;i++)
{
for(int j=1;j<=9;j++)
{
if(s[cnt]=='.')
{
for(int k=1;k<=9;k++)
{
addedge(line,i,j,k);
mp[line]=node{i,j,k};
line++;
}
}
else
{
int now=s[cnt]-'0';
addedge(line,i,j,now);
mp[line]=node{i,j,now};
line++;
}
cnt++;
}
}
dlx.dfs(0);
for(int i=0;i<dlx.cnt;i++)
{
node use=mp[dlx.ans[i]];
a[use.x][use.y]=use.now;
}
for(int i=1;i<=9;i++)
{
for(int j=1;j<=9;j++)
{
printf("%d",a[i][j]);
}
}
putchar('\n');
}
return 0;
}
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