解法1:
#include<iostream>
#include<cstring>
using namespace std;
const int N = 305;
int dx[] = {-1, -1, -1, 0, 0, 1, 1, 1}, dy[] = {-1, 0, 1, -1, 1, -1, 0, 1};
char g[N][N];
int _0[N][N];
int T, n;
void dfs(int x, int y){
_0[x][y] = -1;
for(int i = 0; i < 8; i ++ ){
int a = dx[i] + x, b = dy[i] + y;
if(a >= 0 && b >= 0 && a < n && b < n && _0[a][b] != -1){
if(!_0[a][b]) _0[a][b] = -1, dfs(a, b);
_0[a][b] = -1;
}
}
}
int main(){
cin>>T;
for(int q = 1; q <= T; q ++ ){
int res = 0;
cin>>n;
for(int i = 0; i < n; i ++ ) cin>>g[i];
for(int i = 0; i < n; i ++ )
for(int j = 0; j < n; j ++ ){
if(g[i][j] == '*') _0[i][j] = -1;
else{
_0[i][j] = 0;
for(int k = 0; k < 8; k ++ ){
int a = dx[k] + i, b = dy[k] + j;
if(a >= 0 && b >= 0 && a < n && b < n && g[a][b] == '*')
_0[i][j] ++;
}
}
}
for(int i = 0; i < n; i ++ ){
for(int j = 0; j < n; j ++ ){
if(!_0[i][j]){
res ++;
dfs(i, j);
}
}
}
for(int i = 0; i < n; i ++ )
for(int j = 0; j < n; j ++ )
if(_0[i][j] != -1)
res ++;
printf("Case #%d: %d\n", q, res);
}
return 0;
}
解法2
#include<iostream>
#include<cstring>
using namespace std;
const int N = 305;
int dx[] = {-1, -1, -1, 0, 0, 1, 1, 1}, dy[] = {-1, 0, 1, -1, 1, -1, 0, 1};
char g[N][N];
int _0[N][N];
bool st[N][N];
int T, n;
void dfs(int x, int y){
st[x][y] = true;
for(int i = 0; i < 8; i ++ ){
int a = dx[i] + x, b = dy[i] + y;
if(a >= 0 && b >= 0 && a < n && b < n && !st[a][b] && g[a][b] != '*'){
st[a][b] = true;
if(!_0[a][b]) dfs(a, b);
}
}
}
int main(){
cin>>T;
for(int q = 1; q <= T; q ++ ){
int res = 0;
memset(st, false, sizeof st);
cin>>n;
for(int i = 0; i < n; i ++ ) cin>>g[i];
for(int i = 0; i < n; i ++ ){
for(int j = 0; j < n; j ++ ){
if(g[i][j] == '*') _0[i][j] = -1;
else{
int cou = 0;
for(int k = 0; k < 8; k ++ ){
int a = dx[k] + i, b = dy[k] + j;
if(a >= 0 && b >= 0 && a < n && b < n && g[a][b] == '*') cou ++;
}
_0[i][j] = cou;
}
}
}
for(int i = 0; i < n; i ++ ){
for(int j = 0; j < n; j ++ ){
if(!st[i][j] && !_0[i][j]){
res ++;
dfs(i, j);
}
}
}
for(int i = 0; i < n; i ++ )
for(int j = 0; j < n; j ++ )
if(!st[i][j] && g[i][j] == '.')
res ++;
printf("Case #%d: %d\n", q, res);
}
return 0;
}