poj 1175 starry night#BFS#模拟

Hint

Just to make it clearer, notice that this sample input corresponds to the following picture of the sky. 

Notice that this sample output corresponds to the following picture. 

/**poj 1175 #BFSBFS出每个云团，问题在于处理两个云团是否相同。处理方法是将每个云团映射到[0,0] 到[n,m]的矩阵中，然后就可以旋转或对称操作之后来比较了。*/#include <stdio.h>#include <queue>#include <algorithm>#include <iostream>using namespace std;#define N 555#define M 111#define INF 55555char mat[M][M];struct Point{    int x,y;    Point(int a = 0,int b = 0)    {        x = a;        y = b;    }};bool cmp(Point a,Point b){    if(a.x == b.x)        return a.y < b.y;    return a.x < b.x;}struct node{    int m,n,x,y;    vector<Point> vec;    void draw(char c)    {        int len = vec.size();        for(int i = 0; i < len; ++i)            mat[x+vec[i].x][y+vec[i].y] = c;    }    void push(vector<Point> ve)    {        int minx,miny,maxx,maxy;        minx = miny = INF;        maxx = maxy = -1;        int len = ve.size(),i;        for(i = 0; i < len; ++i)        {            minx = min(minx,ve[i].x);            miny = min(miny,ve[i].y);            maxx = max(maxx,ve[i].x);            maxy = max(maxy,ve[i].y);        }        n = maxx - minx + 1;        m = maxy - miny + 1;        x = minx;        y = miny;        for(i = 0; i < len; ++i)            vec.push_back(Point(ve[i].x-x,ve[i].y-y));        sort(vec.begin(),vec.end(),cmp);    }    void rotate()    {        int i,t,len = vec.size();        for(i = 0; i < len; ++i)        {            t = vec[i].y;            vec[i].y = n - vec[i].x - 1;            vec[i].x = t;        }        swap(m,n);        sort(vec.begin(),vec.end(),cmp);    }    void reservey()    {        int i,len = vec.size();        for(i = 0; i < len; ++i)        {            vec[i].x = n - vec[i].x - 1;        }        sort(vec.begin(),vec.end(),cmp);    }    void reservex()    {        int i,len = vec.size();        for(i = 0; i < len; ++i)            vec[i].y = m - vec[i].y - 1;        sort(vec.begin(),vec.end(),cmp);    }}c[N];bool same(node t,node p){    if(t.m == p.m && t.n == p.n && t.vec.size() == p.vec.size())    {        int i,len = t.vec.size();        for(i = 0; i < len && t.vec[i].x == p.vec[i].x && t.vec[i].y == p.vec[i].y; ++i);        return i == len;    }    return 0;}bool similars(node t,node p){    node pt;    if(t.m != p.m & t.n != p.n && t.m != p.n && t.n != p.m)        return 0;    for(int i = 0; i < 4; ++i)    {        if(same(t,p))            return 1;        pt = p;        pt.reservey();        if(same(t,pt))            return 1;        pt = p;        pt.reservex();        if(same(t,pt))            return 1;        p.rotate();    }    return 0;}int move[][2] = {0,1, 1,0, 0,-1, -1,0, 1,-1, 1,1, -1,1, -1,-1};int n,m;bool ok(int x,int y){    return x >= 0 && x < n && y >= 0 && y < m && mat[x][y] == '1';}vector<Point> bfs(int x,int y){    vector<Point> vv;    Point p(x,y),pt;    queue<Point> que;    int i;    que.push(p);    vv.push_back(p);    mat[x][y] = '0';    while(!que.empty())    {        p = que.front();        que.pop();        for(i = 0; i < 8; ++i)        {            pt = Point(p.x+move[i][0],p.y+move[i][1]);            if(ok(pt.x,pt.y))            {                que.push(pt);                vv.push_back(pt);                mat[pt.x][pt.y] = '0';            }        }    }    return vv;}int vis[N];int main(){    scanf("%d%d",&m,&n);    int i,j,k = 0;    for(i = 0; i < n; ++i)        scanf("%s",mat[i]);    for(i = 0; i < n; ++i)        for(j = 0; j < m; ++j)            if(mat[i][j] =='1')                c[k++].push(bfs(i,j));    char ch = 'a';    for(i = 0; i < k; ++i)    {        if(vis[i])            continue;        vis[i] = 1;        c[i].draw(ch);        for(j = i + 1; j < k; ++j)            if(!vis[j] && similars(c[i],c[j]))            {                c[j].draw(ch);                vis[j] = 1;            }        ++ch;    }    for(i = 0; i < n; ++i)        printf("%s\n",mat[i]);    return 0;}