POJ 1856 Sea Battle (bfs,dfs)

题意：寻找相连的区域，八个方向都要找，判断这个区域是否为矩形。

这题写得太悲剧了，写哭了，bfs写完超时，dfs写完还超时...........最后才发现是在输入处理上出了问题....哎，啥都不说了....都在代码里了........

bfs:

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <memory.h>
#include <cmath>
#include <vector>
using namespace std;

const int BORDER = (1<<26)-1;
#define MAXN 1010
#define INF 0x7ffffff
#define _clr(x,y) memset(x,y,sizeof(x))
#define _add(x) ((++x)&BORDER)
#define _in(x) scanf("%d",&x)
#define _out(x) printf("%d\n",x)
#define _min(m,v) m<v?m:v
#define _max(m,v) m>v?m:v

#define _set_que(q,i,a,b) {q[i].x=a;q[i].y=b;}
#define _set_node(n,a,b) {n.x=a;n.y=b;}

struct NODE{
    int x,y;
}que[BORDER+5],node[MAXN*MAXN];
int index;
int direct[8][2] = {{-1,-1},{-1,0},{-1,1},{0,1},
    {1,1},{1,0},{1,-1},{0,-1}};
int direct1[4][2] = {{0,1},{0,-1},{1,0},{-1,0}};
int visit[MAXN][MAXN];
char arr[MAXN][MAXN];
int n,m,en,st,ans,minx,miny,maxx,maxy;
inline bool _is(const int& x,const int& y)
{
    if(x<0 || x>=n)
        return false;
    if(y<0 || y>=m)
        return false;
    return true;
}
inline void _max_min(const int& a,const int& b)
{
    minx = _min(minx,a);
    miny = _min(miny,b);
    maxx = _max(maxx,a);
    maxy = _max(maxy,b);
}
int init()
{
    en = 1;
    st = 0;
    ans = 0;
    index = 0;
    _clr(visit,0);
    return 0;
}
int bfs(const int& px,const int& py)
{
    int x,y,i,j,tmp,a,b,sum;
    /* init */
    en = 1;
    st = sum = 0;
    visit[px][py] = 1;
    minx = INF;
    miny = INF;
    maxx = -1;
    maxy = -1;
    _set_que(que,0,px,py);
    while(st < en)
    {
        a = que[st].x;
        b = que[st].y;
        _max_min(a,b);    
        ++sum;
        _add(st);
        for(i = 0; i < 8; ++i)
        {
            x = a + direct[i][0];
            y = b + direct[i][1];
            if(_is(x,y) && arr[x][y]=='#' && !visit[x][y])
            {
                visit[x][y] = 1;
                _set_que(que,en,x,y);
                _add(en);
            }
        }
    }
    tmp = (maxx-minx+1)*(maxy-miny+1);
    if(tmp == sum)
        return 1;
    else
        return 0;
}
int main()
{
    int i,j,tmp;
    char str[MAXN];
    while(scanf("%d%d",&n,&m))
    {
        if(!n && !m)
            break;
        init();
        gets(str);
        for(i = 0; i < n; ++i)
            scanf("%s",arr[i]);
        for(i = 0; i < n; ++i)
        {
            for(j = 0; j < m; ++j)
                if(arr[i][j] == '#' && !visit[i][j])
                {
                    tmp = bfs(i,j);
                    if(tmp)
                        ++ans;
                    else
                    {
                        ans = -1;
                        break;
                    }
                }
            if(ans == -1)
                break;
        }
        if(ans == -1)
            printf("Bad placement.\n");
        else
            printf("There are %d ships.\n",ans);
    }
    return 0;
}

dfs:

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <memory.h>
#include <cmath>
#include <vector>
using namespace std;

const int BORDER = (1<<26)-1;
#define MAXN 1010
#define INF 0x7ffffff
#define _clr(x,y) memset(x,y,sizeof(x))
#define _add(x) ((++x)&BORDER)
#define _in(x) scanf("%d",&x)
#define _out(x) printf("%d\n",x)
#define _min(m,v) m<v?m:v
#define _max(m,v) m>v?m:v

#define _set_que(q,i,a,b) {q[i].x=a;q[i].y=b;}
#define _set_node(n,a,b) {n.x=a;n.y=b;}

struct NODE{
    int x,y;
}que[BORDER+5],node[MAXN*MAXN];
int index;
int direct[8][2] = {{-1,-1},{-1,0},{-1,1},{0,1},
    {1,1},{1,0},{1,-1},{0,-1}};
int direct1[4][2] = {{0,1},{0,-1},{1,0},{-1,0}};
int visit[MAXN][MAXN];
char arr[MAXN][MAXN];
int n,m,en,st,ans,minx,miny,maxx,maxy,sum;
inline bool _is(const int& x,const int& y)
{
    if(x<0 || x>=n)
        return false;
    if(y<0 || y>=m)
        return false;
    return true;
}
inline void _max_min(const int& a,const int& b)
{
    minx = _min(minx,a);
    miny = _min(miny,b);
    maxx = _max(maxx,a);
    maxy = _max(maxy,b);
}
int init()
{
    en = 1;
    st = 0;
    ans = 0;
    index = 0;
    _clr(visit,0);
    return 0;
}
int dfs(const int& x,const int& y)
{
    int a,b;
    visit[x][y] = 1;
    ++sum;
    _max_min(x,y);
    for(int i = 0; i < 8; ++i)
    {
        a = x + direct[i][0];
        b = y + direct[i][1];
        if(_is(a,b) && arr[a][b]=='#' && !visit[a][b])
            dfs(a,b);
    }
    return 0;
}
int main()
{
    int i,j,tmp;
    char str[MAXN];
    while(scanf("%d%d",&n,&m))
    {
        if(!n || !m)
            return 0;
        init();
        for(i = 0; i < n; ++i)
        {
            scanf("%s",arr[i]);
        }
        for(i = 0; i < n; ++i)
            for(j = 0; j < m; ++j)
        {
            if(arr[i][j] == '#' && !visit[i][j])
            {
            maxx = maxy = -1;
            minx = miny = INF;
            sum = 0;
            dfs(i,j);
            if( sum == (maxx-minx+1)*(maxy-miny+1) )
                ++ans;
            else
            {
                ans = -1;
                break;
            }
            }
            if(ans == -1)
                break;
        }
        if(ans == -1)
            printf("Bad placement.\n");
        else
            printf("There are %d ships.\n",ans);
    }
    return 0;
}