poj-1856 Sea Battle *

/*
 * bfs
 * 又是一道水题。。1A
 *
 */
#include <cstdio>
#include <cstring>
using namespace std;

const int MAXN = 1000 + 5;
int r, c;        //同题意
bool vis[MAXN][MAXN];
char map[MAXN][MAXN];
// sx,sy:矩形左上角。。ex,ey：矩形右下角..tot：矩形数。。。flag：是否正确
int sx, sy, ex, ey, tot, flag;


//获得ex，ey.. 若不是矩形，返回false
bool inline get_cor(int sxx, int syy, int &exx, int &eyy){
    int i, j;
    for(i=sxx+1; i<r && map[i][syy]=='#'; i++);
    exx = i - 1;
    for(i=syy+1; i<c && map[sxx][i]=='#'; i++);
    eyy = i - 1;

    for(i=sxx; i<=exx; i++){
        for(j=syy; j<=eyy; j++){
            if(map[i][j] != '#') return 0;
            vis[i][j] = 1;
        }
    }

    return 1;
}

//检查矩形四周是否有‘#’
bool check(int sxx, int syy, int exx, int eyy){
    if(sx > 0){
        for(int i = syy-1; i<=eyy+1; i++){
            if(i>=0 && i<c && map[sx-1][i]=='#') return 0;
        }
    }
    if(ex < r-1){
        for(int i = syy-1; i<=eyy+1; i++){
            if(i>=0 && i<c && map[ex+1][i]=='#') return 0;
        }
    }
    if(sy > 0){
        for(int i = sxx-1; i<=exx+1; i++){
            if(i>=0 && i<r && map[i][sy-1]=='#') return 0;
        }
    }
    if(ey < c-1){
        for(int i = sxx-1; i<=exx+1; i++){
            if(i>=0 && i<r && map[i][ey+1]=='#') return 0;
        }
    }
    return 1;
}


int main(){
    while(scanf("%d %d", &r, &c)){
        if(r == 0) return 0;

        getchar();
        for(int i=0; i<r; i++)
            gets(map[i]);

        memset(vis, 0, sizeof(vis));
        tot = 0; flag = 1;

        //遍历
        for(int i=0; i<r; i++){
            for(int j=0; j<c; j++){
                if(map[i][j] == '.' || vis[i][j]) continue;

                sx = i; sy = j;
                if(get_cor(i, j, ex, ey) == 0){
                    flag = 0;
                    i = r; break;
                }
                if(check(sx, sy, ex, ey) == 0){
                    flag = 0;
                    i = r; break;
                }
                tot++;
            }
        }
        if(flag)
            printf("There are %d ships.\n", tot);
        else
            printf("Bad placement.\n");
    }

    return 0;
}