JSFiddle - React, Tailwind, and code Playground

JavaScript

if (confirm("Run Program")) {
    var tosses = 1000000;
    var n = 1; // pin length
    Run();
}
function Run() {
    var crossed = 0;
    var pi;
    for (var i = 0; i < tosses; i++) {
        crossed += DropPin();   
    }
    var pi = 2 * tosses / crossed;  
    alert ("pi= " + pi);
}
function DropPin() {
    var cross = 0;
    var y1 = Math.random();
    var ang = 2 * Math.PI * Math.random();
    var y2 = y1 + n * Math.sin(ang)
    if (y2 >= n || y2 <= 0) {
         cross = 1;
    }
    return cross;
}