HDOJ 4069 Squiggly Sudoku 精确覆盖+搜索

//HDOJ 4069 Squiggly Sudoku 精确覆盖+搜索
/*
题意：数独变形
9块弯弯曲曲的区域 每块有9个小格
往这81个格子里面填写1-9的数字，使得每行，每列，每个区域都含有1、2、3...9

思路：先搜索标记出每一块 再精确覆盖

*/
#include<iostream>
#include<stdio.h>
#include<string.h>
#include<queue>
using namespace std;
#define INF 0x7FFFFFFF
#define N 750
#define M 350
#define V N*M

int n, m, size, row, cnt;
int L[V], R[V], U[V], D[V], C[V] , X[V];
int S[M], Q
, H
;
int s[10][10];
bool map[100][100],vis
;
int dir[][2] = {0,-1,1,0,0,1,-1,0};
int bx[] = {128,64,32,16};
int color[10][10],ans
;
struct node{
int x,y;
};
void init(){
int i;
for (i = 0; i <= m; i++){
S[i] = 0;
L[i + 1] = i;
R[i] = i + 1;
U[i] = D[i] = i;
}
R[m] = 0;
size = m + 1;
}
void remove(int c){
int i, j;
R[L[c]] = R[c];
L[R[c]] = L[c];
for (i = D[c]; i != c; i = D[i]){
for (j = R[i]; j != i; j = R[j]){
D[U[j]] = D[j];
U[D[j]] = U[j];
S[C[j]]--;
}
}
}
void resume(int c){
int i, j;
R[L[c]] = c;
L[R[c]] = c;
for (i = D[c]; i != c; i = D[i]){
for (j = R[i]; j != i; j = R[j]){
U[D[j]] = j;
D[U[j]] = j;
S[C[j]]++;
}
}
}
void Link(int r, int c){
D[size] = D[c];
U[size] = 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]++;
C[size] = c;
X[size++] = r;
}
bool Dance(){
int i, j, c, temp;
if (R[0] == 0){
++cnt;
if(cnt == 1){
for(i = j = 1; i <= row; ++i)
if(vis[i])
ans[j++] = Q[i];
}
return cnt > 1;
}
for (temp = INF, i = R[0]; i; i = R[i]){
if (S[i] < temp){
c = i;
temp = S[i];
}
}
remove(c);
for (i = D[c]; i != c; i = D[i]){
vis[X[i]] = true;
for (j = R[i]; j != i; j = R[j])
remove(C[j]);
if (Dance())
return true;
for (j = L[i]; j != i; j = L[j])
resume(C[j]);
vis[X[i]] = false;
}
resume(c);
return false;
}
bool check(int x,int y){
if(x>=1 && x<=9 && y>=1 && y<=9)
return true;
return false;
}
void Init(){
int i,j,k,x,y;
memset(map,false,sizeof(map));
for(i = 1; i <= 9; ++i){
for(j = 1; j <= 9; ++j){
scanf("%d",&s[i][j]);
for(k = 0; k < 4; ++k){
if(s[i][j] >= bx[k])
s[i][j] -= bx[k];
else{
x = i + dir[k][0];
y = j + dir[k][1];
if(check(x,y))
map[(i-1)*9+j][(x-1)*9+y] = true;
}
}
}
}
}
void bfs(int x,int y,int c){
int k;
queue<node>Q;
node p,q;
p.x = x;
p.y = y;
Q.push(p);
while(!Q.empty()){
q = Q.front();
Q.pop();
for(k = 0; k < 4; ++k){
p.x = q.x + dir[k][0];
p.y = q.y + dir[k][1];
if(check(p.x,p.y) && map[(q.x-1)*9+q.y][(p.x-1)*9+p.y] && color[p.x][p.y]==-1){
color[p.x][p.y] = c;
Q.push(p);
}
}
}
}
void Color(){
int i,j,num = 0;
memset(color,-1,sizeof(color));
for(i = 1; i <= 9; ++i)
for(j = 1; j <= 9; ++j){
if(color[i][j] == -1){
color[i][j] = num;
bfs(i,j,num);
num++;
}
}
}
void Build(){
init();
int i,j,k;
row = 0;
for(i = 1; i <= 9; ++i){
for(j = 1; j <= 9; ++j){
if(s[i][j] == 0){
for(k = 1; k <= 9; ++k){
H[++row] = -1;
Q[row] = k;
Link(row,(i-1)*9+k);
Link(row,81+(j-1)*9+k);
Link(row,162+color[i][j]*9+k);
Link(row,243+(i-1)*9+j);
}
}
else{
H[++row] = -1;
k = s[i][j];
Q[row] = k;
Link(row,(i-1)*9+k);
Link(row,81+(j-1)*9+k);
Link(row,162+color[i][j]*9+k);
Link(row,243+(i-1)*9+j);
}
}
}

}
int main(){
int T,i,j,num,ca = 1;
int x,y;
m = 324;
scanf("%d",&T);
while(T--){
Init();
Color();
Build();
memset(vis,false,sizeof(vis));
cnt = 0;
Dance();
printf("Case %d:\n",ca++);
if(cnt == 0)
puts("No solution");
else if(cnt > 1)
puts("Multiple Solutions");
else{
num = 1;
for(i = 1; i <= 9; ++i){
for(j = 1; j <= 9; ++j){
printf("%d",ans[num]);
if(num%9 == 0)
puts("");
num++;
}
}
}
}
return 0;
}