JSFiddle - React, Tailwind, and code Playground

by wangtn18

JavaScript

var coordinates = {
     "a": [
         [1, 2],
         [8, 9],
         [3, 5],
         [6, 1]
     ],

         "b": [
         [5, 8],
         [2, 4],
         [6, 8],
         [1, 9]
     ]
 };
alert(Object.keys(coordinates).length);
/* for (var i = 0; i < coordinates.length; i++) {
     alert(i);
 }*/