fix.js

function buildFunctions() {
    var arr = [];
 
    for (var i = 0; i < 3; i++) {
        arr.push((function(j) {
            return function() {
                console.log(j);
            };
        }(i)));
    }
 
    return arr;
}
 
var fs = buildFunctions();
 
fs[0]();
fs[1]();
fs[2]();