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/*! This file exists only for testing a Minify installation. Its content is not used. |
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* |
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* http://example.org/min/f=min/quick-test.js |
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*/ |
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|
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/* Finds the lowest common multiple of two numbers */ |
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function LCMCalculator(x, y) { // constructor function |
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var checkInt = function (x) { // inner function |
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if (x % 1 !== 0) { |
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throw new TypeError(x + " is not an integer"); // throw an exception |
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} |
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return x; |
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}; |
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this.a = checkInt(x); |
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// ^ semicolons are optional |
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this.b = checkInt(y); |
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} |
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// The prototype of object instances created by a constructor is |
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// that constructor's "prototype" property. |
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LCMCalculator.prototype = { // object literal |
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constructor: LCMCalculator, // when reassigning a prototype, set the constructor property appropriately |
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gcd: function () { // method that calculates the greatest common divisor |
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// Euclidean algorithm: |
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var a = Math.abs(this.a), b = Math.abs(this.b), t; |
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if (a < b) { |
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// swap variables |
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t = b; |
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b = a; |
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a = t; |
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} |
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while (b !== 0) { |
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t = b; |
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b = a % b; |
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a = t; |
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} |
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// Only need to calculate GCD once, so "redefine" this method. |
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// (Actually not redefinition - it's defined on the instance itself, |
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// so that this.gcd refers to this "redefinition" instead of LCMCalculator.prototype.gcd.) |
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// Also, 'gcd' === "gcd", this['gcd'] === this.gcd |
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this['gcd'] = function () { |
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return a; |
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}; |
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return a; |
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}, |
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// Object property names can be specified by strings delimited by double (") or single (') quotes. |
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"lcm" : function () { |
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// Variable names don't collide with object properties, e.g. |lcm| is not |this.lcm|. |
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// not using |this.a * this.b| to avoid FP precision issues |
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var lcm = this.a / this.gcd() * this.b; |
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// Only need to calculate lcm once, so "redefine" this method. |
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this.lcm = function () { |
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return lcm; |
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}; |
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return lcm; |
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}, |
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toString: function () { |
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return "LCMCalculator: a = " + this.a + ", b = " + this.b; |
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} |
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}; |
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|
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//define generic output function; this implementation only works for web browsers |
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function output(x) { |
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document.write(x + "<br>"); |
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} |
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|
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// Note: Array's map() and forEach() are defined in JavaScript 1.6. |
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// They are used here to demonstrate JavaScript's inherent functional nature. |
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[[25, 55], [21, 56], [22, 58], [28, 56]].map(function (pair) { // array literal + mapping function |
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return new LCMCalculator(pair[0], pair[1]); |
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}).sort(function (a, b) { // sort with this comparative function |
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return a.lcm() - b.lcm(); |
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}).forEach(function (obj) { |
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output(obj + ", gcd = " + obj.gcd() + ", lcm = " + obj.lcm()); |
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}); |
