SLG, 菱形格子的算法.(递归版

class GeoPoint{
public:
    int x;
    int y;
    
public:
    bool operator == (const GeoPoint& p){
        return p.x == this->x && p.y == this->y;
    }
    GeoPoint(int x, int y):x(x), y(y){
    }
};


void findGrids(int x, int y, int limit, std::vector<GeoPoint>& list){
    
    if(limit <= 0){
        return;
    }
    
    if(std::find(list.begin(), list.end(), GeoPoint(x, y)) == list.end()){
    
        list.push_back(GeoPoint(x, y));
    }
    findGrids(x, y + 1, limit - 1, list);
    findGrids(x, y - 1, limit - 1, list);
    findGrids(x - 1, y, limit - 1, list);
    findGrids(x + 1, y, limit - 1, list);
        
    
    
}
void main(){
    std::vector<GeoPoint> rangeList;
    int x = 3;
    int y = 2;
    int r = 3;
    findGrids(x, y, r, rangeList);
}

记得好久以前看过一个日本人写的算法..非常赞..但是以前看不懂,,不过记得很清楚..就是效率非常的快.

而且边扩张边保存自带中心点到目的点的路径....

= =今晚试下能不能模仿一个...

先写一个最基本的算法