lz77-alike

main.js

(function decompress (s) {
  var i, c, out = "", len, offset;
  for (i = 0; i < s.length; i++) {
    c = s.charCodeAt(i);
    if (c >= 256 && c <= 288) {
      len = c - 256;
      offset = s.charCodeAt(++i);
      out += out.substr(-offset, len);
    } else {
      out += s.charAt(i);
    }
  }
  return decodeURIComponent(escape(out));
}(function compress (s) {
  var i, out = [], tmp, p, b;
  s = unescape(encodeURIComponent(s));
  for (i = 0; i < s.length; i++) {
    for (b = 64; b >= 4; b--) {
      tmp = s.substr(i, b);
      p = s.slice(0, i).indexOf(tmp);
      if (p > -1) {
        out.push(256 + b, i-p);
        i += b-1;
        break;
      }
    }
    if (b === 3) out.push(s.charCodeAt(i));
  }
  return out;
}(str)))

(function huffman (s) {
  var i, c, h = {}, a = [];
  for (i = s.length-1; i >= 0; i--) {
    c = s.charCodeAt(i);
    h[c] = (h[c] || 0) + 1;
  }
  for (c in h) a.push([parseInt(c), h[c]]);
  a.sort(function(a,b){ return b[1]-a[1] });
  var n,n1,n2;
  while (a.length > 2) {
    n = [[n2 = a.pop(), n1 = a.pop()], n1[1] + n2[1]]
    for (i = a.length - 1; i >= 0 && a[i][1] < n[1]; i--);
    a.splice(i,0,n);
  }
  var bits = [];
  (function r (node, m, d) {
    if (typeof node[0] === 'number') {
      bits.push(1, node[0]);
    } else {
      bits.push(0);
      r(node[0][0], m*2,   d+1);
      r(node[0][1], m*2+1, d+1);
    }
  }([a, a[0][1] + a[1][1]]), 0, 0);
  return bits;
}("j'aime aller sur le bord de l'eau les jeudis ou les jours impairs"))

function(t){var a=[],f=0,b=0,s=function(l,n){for(f+=n<<b,b+=l;b>t;b-=t,f>>=t)a.push(f%(1<<t))}s.e=function(){return b&&a.push(f),a}return s}