JSFiddle - React, Tailwind, and code Playground

JavaScript

var obj = {x:30,y:20};
    var arr = [];
    for(var i = 0;i<3;i++) {
        arr.push({x:obj.x, y:obj.y});
    }
    arr[0].y = 40;
    document.write(arr[0].y + " " + arr[1].y);