Getting sum halstead effort from jscomplexity.org

gistfile1.js

var labels = document.querySelectorAll('.label');
var matchedLabels = [];
for (var i = 0; i < labels.length; i++) {
    if (labels[i].innerText.match('Halstead effort')) {
        matchedLabels.push(labels[i]);
    }
}

matchedLabels.reduce(function(memo, item) {
    var value = item.parentNode.querySelector('.value').innerText * 1;
    return memo + value
}, 0)