var slides = [];

function slide(x) {
    slides.push(
        (function(s) {
            return function() {
                window.location.hash = s;
                document.body.style.cssText = window.oc;
                x();
            };
        })(slides.length)
    );
}

function main(text) {
    return function() {
        document.body.innerHTML = text;
    };
}

function big(x) {
    return function() {
        x();
        var i = 1e3, e = document.body;
        e.style.display = 'inline';
        e.style.fontSize = i + 'px';
        while (
            e.offsetWidth > window.innerWidth ||
            e.offsetHeight > window.innerHeight) {
            e.style.fontSize = (i -= 10) + 'px';
        }
    }
}

window.onload = function() {
    var doc = document,
        win = window,
        cur = (win.location.hash && parse_hash()) || 0;

    win.oc = doc.body.style.cssText;

    function parse_hash() {
        return Math.max(Math.min(
            slides.length - 1,
            parseInt(win.location.hash.substring(1), 10)), 0);
    }

    doc.onkeydown = function(e) {
        (e.which === 39) && slides[cur = Math.min(slides.length - 1, ++cur)]();
        (e.which === 37) && slides[cur = Math.max(0, --cur)]();
    };

    doc.onclick = doc.ontouchstart = function() {
        slides[cur = Math.min(slides.length - 1, ++cur)]();
    };

    win.onhashchange = function() {
        var c = parse_hash();
        if (c !== cur) slides[cur = c]();
    };

    slides[cur]();
};