JSFiddle - React, Tailwind, and code Playground

HTML

<button id="btn-0">Click</button>
<button id="btn-1">Click</button>
<button id="btn-2">Click</button>
<button id="btn-3">Click</button>

JavaScript

var arr = [ [0], [1], [2], [3] ];
    for ( var i = 0; i < arr.length; i++ ) {
        var j = function(x) {
          $('#btn-' + x).click(function() {
            console.log(x);
          });
        }
        j(i);    
    }