function numberToHex(num)
{
    var hexArray = "0123456789abcdef";
    str = "";
    for(j = 0; j <= 3; j++)
    str += hexArray.charAt((num >> (j * 8 + 4)) & 0x0F) +
           hexArray.charAt((num >> (j * 8)) & 0x0F);
    return str;
}

function stringToBlock(str)
{
    nblk = ((str.length + 8) >> 6) + 1;
    blks = new Array(nblk * 16);
    for(i = 0; i < nblk * 16; i++) blks[i] = 0;
    for(i = 0; i < str.length; i++)
    blks[i >> 2] |= str.charCodeAt(i) << ((i % 4) * 8);
    blks[i >> 2] |= 0x80 << ((i % 4) * 8);
    blks[nblk * 16 - 2] = str.length * 8;
    return blks;
}


function add(x, y)
{
    var lsw = (x & 0xFFFF) + (y & 0xFFFF);
    var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
    return (msw << 16) | (lsw & 0xFFFF);
}

function rol(num, cnt)
{
    return (num << cnt) | (num >>> (32 - cnt));
}

function command(q, a, b, x, s, t)
{
    return add(rol(add(add(a, q), add(x, t)), s), b);
}

function ff(a, b, c, d, x, s, t)
{
    return command((b & c) | ((~b) & d), a, b, x, s, t);
}

function gg(a, b, c, d, x, s, t)
{
    return command((b & d) | (c & (~d)), a, b, x, s, t);
}

function hh(a, b, c, d, x, s, t)
{
    return command(b ^ c ^ d, a, b, x, s, t);
}

function ii(a, b, c, d, x, s, t)
{
    return command(c ^ (b | (~d)), a, b, x, s, t);
}


function md5Hash(str)
{
    x = stringToBlock(str);
    var a =  1732584193;
    var b = -271733879;
    var c = -1732584194;
    var d =  271733878;

    for(i = 0; i < x.length; i += 16)
    {
        var olda = a;
        var oldb = b;
        var oldc = c;
        var oldd = d;

        a = ff(a, b, c, d, x[i+ 0], 7 , -680876936);
        d = ff(d, a, b, c, x[i+ 1], 12, -389564586);
        c = ff(c, d, a, b, x[i+ 2], 17,  606105819);
        b = ff(b, c, d, a, x[i+ 3], 22, -1044525330);
        a = ff(a, b, c, d, x[i+ 4], 7 , -176418897);
        d = ff(d, a, b, c, x[i+ 5], 12,  1200080426);
        c = ff(c, d, a, b, x[i+ 6], 17, -1473231341);
        b = ff(b, c, d, a, x[i+ 7], 22, -45705983);
        a = ff(a, b, c, d, x[i+ 8], 7 ,  1770035416);
        d = ff(d, a, b, c, x[i+ 9], 12, -1958414417);
        c = ff(c, d, a, b, x[i+10], 17, -42063);
        b = ff(b, c, d, a, x[i+11], 22, -1990404162);
        a = ff(a, b, c, d, x[i+12], 7 ,  1804603682);
        d = ff(d, a, b, c, x[i+13], 12, -40341101);
        c = ff(c, d, a, b, x[i+14], 17, -1502002290);
        b = ff(b, c, d, a, x[i+15], 22,  1236535329);    

        a = gg(a, b, c, d, x[i+ 1], 5 , -165796510);
        d = gg(d, a, b, c, x[i+ 6], 9 , -1069501632);
        c = gg(c, d, a, b, x[i+11], 14,  643717713);
        b = gg(b, c, d, a, x[i+ 0], 20, -373897302);
        a = gg(a, b, c, d, x[i+ 5], 5 , -701558691);
        d = gg(d, a, b, c, x[i+10], 9 ,  38016083);
        c = gg(c, d, a, b, x[i+15], 14, -660478335);
        b = gg(b, c, d, a, x[i+ 4], 20, -405537848);
        a = gg(a, b, c, d, x[i+ 9], 5 ,  568446438);
        d = gg(d, a, b, c, x[i+14], 9 , -1019803690);
        c = gg(c, d, a, b, x[i+ 3], 14, -187363961);
        b = gg(b, c, d, a, x[i+ 8], 20,  1163531501);
        a = gg(a, b, c, d, x[i+13], 5 , -1444681467);
        d = gg(d, a, b, c, x[i+ 2], 9 , -51403784);
        c = gg(c, d, a, b, x[i+ 7], 14,  1735328473);
        b = gg(b, c, d, a, x[i+12], 20, -1926607734);

        a = hh(a, b, c, d, x[i+ 5], 4 , -378558);
        d = hh(d, a, b, c, x[i+ 8], 11, -2022574463);
        c = hh(c, d, a, b, x[i+11], 16,  1839030562);
        b = hh(b, c, d, a, x[i+14], 23, -35309556);
        a = hh(a, b, c, d, x[i+ 1], 4 , -1530992060);
        d = hh(d, a, b, c, x[i+ 4], 11,  1272893353);
        c = hh(c, d, a, b, x[i+ 7], 16, -155497632);
        b = hh(b, c, d, a, x[i+10], 23, -1094730640);
        a = hh(a, b, c, d, x[i+13], 4 ,  681279174);
        d = hh(d, a, b, c, x[i+ 0], 11, -358537222);
        c = hh(c, d, a, b, x[i+ 3], 16, -722521979);
        b = hh(b, c, d, a, x[i+ 6], 23,  76029189);
        a = hh(a, b, c, d, x[i+ 9], 4 , -640364487);
        d = hh(d, a, b, c, x[i+12], 11, -421815835);
        c = hh(c, d, a, b, x[i+15], 16,  530742520);
        b = hh(b, c, d, a, x[i+ 2], 23, -995338651);

        a = ii(a, b, c, d, x[i+ 0], 6 , -198630844);
        d = ii(d, a, b, c, x[i+ 7], 10,  1126891415);
        c = ii(c, d, a, b, x[i+14], 15, -1416354905);
        b = ii(b, c, d, a, x[i+ 5], 21, -57434055);
        a = ii(a, b, c, d, x[i+12], 6 ,  1700485571);
        d = ii(d, a, b, c, x[i+ 3], 10, -1894986606);
        c = ii(c, d, a, b, x[i+10], 15, -1051523);
        b = ii(b, c, d, a, x[i+ 1], 21, -2054922799);
        a = ii(a, b, c, d, x[i+ 8], 6 ,  1873313359);
        d = ii(d, a, b, c, x[i+15], 10, -30611744);
        c = ii(c, d, a, b, x[i+ 6], 15, -1560198380);
        b = ii(b, c, d, a, x[i+13], 21,  1309151649);
        a = ii(a, b, c, d, x[i+ 4], 6 , -145523070);
        d = ii(d, a, b, c, x[i+11], 10, -1120210379);
        c = ii(c, d, a, b, x[i+ 2], 15,  718787259);
        b = ii(b, c, d, a, x[i+ 9], 21, -343485551);

        a = add(a, olda);
        b = add(b, oldb);
        c = add(c, oldc);
        d = add(d, oldd);
    }
    var ret = numberToHex(a) + numberToHex(b) + numberToHex(c) + numberToHex(d);
    return ret;
}