// ==UserScript==
// @name	TopRandomPics
// @include	http://forums.topcoder.com/*
// @include	https://forums.topcoder.com/*
// ==/UserScript==

var as = document.getElementsByTagName("img");
for(n=0;n<as.length;++n) {
    var g = as[n].src.match(/(.*_big)([0-9]+)(\.jpg)/);
    if (g != null) {
        var count = g[2];
        var num = Math.floor(Math.random() * count);
        if (num == 0) {
            num = '';
        } else {
            num = num + 1;
        }
        as[n].src = g[1] + num + g[3];
    }
}