言己
原本的 
白色区域是通过 小圆形拼起来的 `circle(map_img, Point(xlist[i]+r, ylist[i]+r), r, Scalar(255), lane_width);`
function unique(a) { return Array.from(new Set(a)); } var a = [{name: "hanzichi"}, {name: "hanzichi"},{age: 30}, new String(1), new Number(1)]; var ans = unique(a); console.log(JSON.stringify(ans)); //output [{"name":"hanzichi"},{"name":"hanzichi"},{"age":30},"1",1]