#include <list>

    struct Grass {
        struct {
            int x, y;
        } position;
    };

    int main() {
        std::list<Grass> grassList;
        for(int i=0;i<50;i++){
            for(int j=0;j<50;j++){
                Grass g1;
                g1.position.x = i;
                g1.position.y = j;
                grassList.push_back(g1);
            }
        }  
    }