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);
}

记得好久曾经看过一个日本人写的算法..很赞..可是曾经看不懂,,只是记得很清楚..就是效率很的快.

并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...

先写一个最主要的算法