加密
function _compress(e, t, n) {
if (null == e)
return "";
var r, o, i, a = {}, s = {}, c = "", u = "", l = "", d = 2, f = 3, p = 2, h = [], v = 0, m = 0;
for (i = 0; i < e.length; i += 1)
if (c = e.charAt(i),
Object.prototype.hasOwnProperty.call(a, c) || (a[c] = f++,
s[c] = !0),
u = l + c,
Object.prototype.hasOwnProperty.call(a, u))
l = u;
else {
if (Object.prototype.hasOwnProperty.call(s, l)) {
if (l.charCodeAt(0) < 256) {
for (r = 0; r < p; r++)
v <<= 1,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++;
for (o = l.charCodeAt(0),
r = 0; r < 8; r++)
v = v << 1 | 1 & o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o >>= 1
} else {
for (o = 1,
r = 0; r < p; r++)
v = v << 1 | o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o = 0;
for (o = l.charCodeAt(0),
r = 0; r < 16; r++)
v = v << 1 | 1 & o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o >>= 1
}
0 == --d && (d = Math.pow(2, p),
p++),
delete s[l]
} else
for (o = a[l],
r = 0; r < p; r++)
v = v << 1 | 1 & o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o >>= 1;
0 == --d && (d = Math.pow(2, p),
p++),
a[u] = f++,
l = String(c)
}
if ("" !== l) {
if (Object.prototype.hasOwnProperty.call(s, l)) {
if (l.charCodeAt(0) < 256) {
for (r = 0; r < p; r++)
v <<= 1,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++;
for (o = l.charCodeAt(0),
r = 0; r < 8; r++)
v = v << 1 | 1 & o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o >>= 1
} else {
for (o = 1,
r = 0; r < p; r++)
v = v << 1 | o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o = 0;
for (o = l.charCodeAt(0),
r = 0; r < 16; r++)
v = v << 1 | 1 & o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o >>= 1
}
0 == --d && (d = Math.pow(2, p),
p++),
delete s[l]
} else
for (o = a[l],
r = 0; r < p; r++)
v = v << 1 | 1 & o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o >>= 1;
0 == --d && (d = Math.pow(2, p),
p++)
}
for (o = 2,
r = 0; r < p; r++)
v = v << 1 | 1 & o,
m == t - 1 ? (m = 0,
h.push(n(v)),
v = 0) : m++,
o >>= 1;
for (; ; ) {
if (v <<= 1,
m == t - 1) {
h.push(n(v));
break
}
m++
}
return h.join("")
};
var n = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+-$';
_compress(
'{"5":{"p":2,"pp":25}}',
6, (function(e) {
return n.charAt(e)
}
)
)
解密
function _decompress(t, n, r) {
var o, i, a, s, c, u, l, d = [], f = 4, p = 4, h = 3, v = "", m = [], g = {
val: r(0),
position: n,
index: 1
};
for (o = 0; o < 3; o += 1)
d[o] = o;
for (a = 0,
c = Math.pow(2, 2),
u = 1; u != c; )
s = g.val & g.position,
g.position >>= 1,
0 == g.position && (g.position = n,
g.val = r(g.index++)),
a |= (s > 0 ? 1 : 0) * u,
u <<= 1;
switch (a) {
case 0:
for (a = 0,
c = Math.pow(2, 8),
u = 1; u != c; )
s = g.val & g.position,
g.position >>= 1,
0 == g.position && (g.position = n,
g.val = r(g.index++)),
a |= (s > 0 ? 1 : 0) * u,
u <<= 1;
l = e(a);
break;
case 1:
for (a = 0,
c = Math.pow(2, 16),
u = 1; u != c; )
s = g.val & g.position,
g.position >>= 1,
0 == g.position && (g.position = n,
g.val = r(g.index++)),
a |= (s > 0 ? 1 : 0) * u,
u <<= 1;
l = e(a);
break;
case 2:
return ""
}
for (d[3] = l,
i = l,
m.push(l); ; ) {
if (g.index > t)
return "";
for (a = 0,
c = Math.pow(2, h),
u = 1; u != c; )
s = g.val & g.position,
g.position >>= 1,
0 == g.position && (g.position = n,
g.val = r(g.index++)),
a |= (s > 0 ? 1 : 0) * u,
u <<= 1;
switch (l = a) {
case 0:
for (a = 0,
c = Math.pow(2, 8),
u = 1; u != c; )
s = g.val & g.position,
g.position >>= 1,
0 == g.position && (g.position = n,
g.val = r(g.index++)),
a |= (s > 0 ? 1 : 0) * u,
u <<= 1;
d[p++] = e(a),
l = p - 1,
f--;
break;
case 1:
for (a = 0,
c = Math.pow(2, 16),
u = 1; u != c; )
s = g.val & g.position,
g.position >>= 1,
0 == g.position && (g.position = n,
g.val = r(g.index++)),
a |= (s > 0 ? 1 : 0) * u,
u <<= 1;
d[p++] = e(a),
l = p - 1,
f--;
break;
case 2:
return m.join("")
}
if (0 == f && (f = Math.pow(2, h),
h++),
d[l])
v = d[l];
else {
if (l !== p)
return null;
v = i + i.charAt(0)
}
m.push(v),
d[p++] = i + v.charAt(0),
i = v,
0 == --f && (f = Math.pow(2, h),
h++)
}
};
var e = String.fromCharCode
, t = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="
, n = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+-$"
, r = {};
function o(e, t) {
if (!r[e]) {
r[e] = {};
for (var n = 0; n < e.length; n++)
r[e][e.charAt(n)] = n
}
return r[e][t]
};
function decompressFromEncodedURIComponent(e) {
return (e = e.replace(/ /g, "+"),
_decompress(e.length, 32, (function(t) {
return o(n, e.charAt(t))
}
)))
};
let aa = decompressFromEncodedURIComponent('N4IgrCBcoA5QTAGhDOl5gL6aA');
console.log(aa);
标签：index,加密,val,++,pow,样例,解密,&&,position From： https://www.cnblogs.com/angdh/p/17472842.html