谷歌翻译js逆向获取tk值

之前有分享过百度翻译获取sign值得帖子，搜狗的tk值应该也类似。不过目前用的网络上免费的资源，如果哪天不能用了，打算研究一下，这里转载一下网上的tk值js函数

function tk(a) {
	var k = "";
	var b = 406644;
	var b1 = 3293161072;
	var jd = ".";
	var $b = "+-a^+6";
	var Zb = "+-3^+b+-f";
	for (var e = [], f = 0, g = 0; g < a.length; g++) { var m = a.charCodeAt(g); 128 > m ? e[f++] = m : (2048 > m ? e[f++] = m >> 6 | 192 : (55296 == (m & 64512) && g + 1 < a.length && 56320 == (a.charCodeAt(g + 1) & 64512) ? (m = 65536 + ((m & 1023) << 10) + (a.charCodeAt(++g) & 1023), e[f++] = m >> 18 | 240,
		e[f++] = m >> 12 & 63 | 128) : e[f++] = m >> 12 | 224,
		e[f++] = m >> 6 & 63 | 128),
		e[f++] = m & 63 | 128)
	}
	a = b;
	for (f = 0; f < e.length; f++) a += e[f], a = RL(a, $b);a = RL(a, Zb);a ^= b1 || 0; 0 > a && (a = (a & 2147483647) + 2147483648);
	a %= 1E6;
	return a.toString() + jd + (a ^ b)
	};

function RL(a, b) {
	var t = "a";
	var Yb = "+";
	for (var c = 0; c < b.length - 2; c += 3) { var d = b.charAt(c + 2), d = d >= t ? d.charCodeAt(0) - 87 : Number(d),
		d = b.charAt(c + 1) == Yb ? a >>> d: a << d;
		a = b.charAt(c) == Yb ? a + d & 4294967295 : a ^ d
	}
	return a
}