The Tor Browser: js/src/tests/ecma_6/Comprehensions/sudoku.js@129ffea94266 (annotated)

js/src/tests/ecma_6/Comprehensions/sudoku.js@129ffea94266 (annotated)

js/src/tests/ecma_6/Comprehensions/sudoku.js

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 function copy(obj) {
   var o = {};
   for (var i in obj)
     o[i] = obj[i];
   return o;
 }
 Array.prototype.contains = String.prototype.contains = function (e) {
   for (var elt of this)
     if (elt == e)
       return true;
   return false;
 }
 Array.prototype.repeat = String.prototype.repeat = function (n) {
   var s = this.constructor();
   for (var i = 0; i < n; i++)
     s = s.concat(this);
   return s;
 }
 String.prototype.center = function (w) {
   var n = this.length;
   if (w <= n)
     return this;
   var m = Math.floor((w - n) / 2);
   return ' '.repeat(m) + this + ' '.repeat(w - n - m);
 }
 Array.prototype.toString = Array.prototype.toSource
 Object.prototype.toString = Object.prototype.toSource
 function all(seq) {
   for (var e of seq)
     if (!e)
       return false;
   return true;
 }
 function some(seq) {
   for (var e of seq)
     if (e)
       return e;
   return false;
 }
 function cross(A, B) {
   return [for (a of A) for (b of B) a+b];
 }
 function dict(A) {
   var d = {};
   for (var e of A)
     d[e[0]] = e[1];
   return d;
 }
 function set(A) {
   var s = [];
   for (var e of A)
     if (!s.contains(e))
       s.push(e);
   return s;
 }
 function zip(A, B) {
   var z = [];
   var n = Math.min(A.length, B.length);
   for (var i = 0; i < n; i++)
     z.push([A[i], B[i]]);
   return z;
 }
 rows = 'ABCDEFGHI';
 cols = '123456789';
 digits   = '123456789';
 squares  = cross(rows, cols);
 unitlist = [for (c of cols) cross(rows, c)]
   .concat([for (r of rows) cross(r, cols)])
   .concat([for (rs of ['ABC','DEF','GHI']) for (cs of ['123','456','789']) cross(rs, cs)]);
 units = dict((for (s of squares)
                 [s, [for (u of unitlist) if (u.contains(s)) u]]));
 peers = dict((for (s of squares)
                 [s, set([for (u of units[s]) for (s2 of u) if (s2 != s) s2])]));
 // Given a string of 81 digits (or . or 0 or -), return a dict of {cell:values}.
 function parse_grid(grid) {
   grid = [for (c of grid) if ('0.-123456789'.contains(c)) c];
   var values = dict((for (s of squares) [s, digits]));
   for (var pair of zip(squares, grid)) {
     var s = pair[0], d = pair[1];
     if (digits.contains(d) && !assign(values, s, d))
       return false;
   }
   return values;
 }
 // Eliminate all the other values (except d) from values[s] and propagate.
 function assign(values, s, d) {
   if (all((for (d2 of values[s]) if (d2 != d) eliminate(values, s, d2))))
     return values;
   return false;
 }
 // Eliminate d from values[s]; propagate when values or places <= 2.
 function eliminate(values, s, d) {
   if (!values[s].contains(d))
     return values; // Already eliminated
   values[s] = values[s].replace(d, '');
   if (values[s].length == 0)
     return false;  // Contradiction: removed last value
   if (values[s].length == 1) {
     // If there is only one value (d2) left in square, remove it from peers
     var d2 = values[s][0];
     if (!all((for (s2 of peers[s]) eliminate(values, s2, d2))))
       return false;
   }
   // Now check the places where d appears in the units of s
   for (var u of units[s]) {
     var dplaces = [for (s of u) if (values[s].contains(d)) s];
     if (dplaces.length == 0)
       return false;
     if (dplaces.length == 1)
 	    // d can only be in one place in unit; assign it there
       if (!assign(values, dplaces[0], d))
         return false;
   }
   return values;
 }
 // Used for debugging.
 function print_board(values) {
   var width = 1 + Math.max.apply(Math, [for (s of squares) values[s].length]);
   var line = '\n' + ['-'.repeat(width*3)].repeat(3).join('+');
   for (var r of rows)
     print([for (c of cols)
               values[r+c].center(width) + ('36'.contains(c) && '|' || '')]
           .join('') + ('CF'.contains(r) && line || ''));
   print('\n');
 }
 easy = "..3.2.6..9..3.5..1..18.64....81.29..7.......8..67.82....26.95..8..2.3..9..5.1.3..";
 print_board(parse_grid(easy));
 // Using depth-first search and constraint propagation, try all possible values.
 function search(values) {
   if (!values)
     return false;    // Failed earlier
   if (all((for (s of squares) values[s].length == 1)))
     return values;   // Solved!
   // Choose the unfilled square s with the fewest possibilities
   // XXX Math.min etc. should work with generator expressions and other iterators
   // XXX Math.min etc. should work on arrays (lists or tuples in Python) as well as numbers
   var a = [for (s of squares) if (values[s].length > 1) values[s].length + s].sort();
   var s = a[0].slice(-2);
   return some((for (d of values[s]) search(assign(copy(values), s, d))));
 }
 hard = '4.....8.5.3..........7......2.....6.....8.4......1.......6.3.7.5..2.....1.4......';
 print_board(search(parse_grid(hard)))
 if (typeof reportCompare === "function")
   reportCompare(true, true);