var colors = ['rgb(191, 191, 191)', 'rgb(254, 76, 97)', 'rgb(243, 156, 17)', 'rgb(255, 193, 22)', 'rgb(82, 196, 26)', 'rgb(52, 152, 219)', 'rgb(157, 61, 207)', 'rgb(14, 29, 105)'];
(function() {
'use strict';
var problems = [];
for(var passed of window._feInjection.currentData.passedProblems) problems.push({pid: passed.pid, dif: passed.difficulty, rendered: false});
for(var tryed of window._feInjection.currentData.submittedProblems) problems.push({pid: tryed.pid, dif: tryed.difficulty, rendered: false});
setInterval(() => {
if(window.location.href.split("#").length == 2 && window.location.href.split("#")[1] == 'practice'){
    for(var i = 0;i < problems.length;i++) if(!problems[i].rendered) {
        var elements = document.querySelectorAll('a');
        for(var el of elements) if(el.textContent == problems[i].pid) {
            if (el.classList) el.classList.remove("color-default");
            else el.className = el.className.replace('color-default',  ' ');
            problems[i].rendered = true;
            el.style.color = colors[problems[i].dif];
            break;
        }
    }
}else for(var j = 0;j < problems.length;j++) problems[j].rendered = false;
}, 1000);
})();

看的吴彦儒主页发现此代码，请问此代码怎么用