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"title" : "Function Composition" ,
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"content" : "<p>Given an array of functions <code>[f<span style=\"font-size: 10.8333px;\">1</span>, f<sub>2</sub>, f<sub>3</sub>, ..., f<sub>n</sub>]</code>, return a new function <code>fn</code> that is the <strong>function composition</strong> of the array of functions.</p>\n\n<p>The <strong>function composition</strong> of <code>[f(x), g(x), h(x)]</code> is <code>fn(x) = f(g(h(x)))</code>.</p>\n\n<p>The <strong>function composition</strong> of an empty list of functions is the <strong>identity function</strong> <code>f(x) = x</code>.</p>\n\n<p>You may assume each function in the array accepts one integer as input and returns one integer as output.</p>\n\n<p> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> functions = [x => x + 1, x => x * x, x => 2 * x], x = 4\n<strong>Output:</strong> 65\n<strong>Explanation:</strong>\nEvaluating from right to left ...\nStarting with x = 4.\n2 * (4) = 8\n(8) * (8) = 64\n(64) + 1 = 65\n</pre>\n\n<p><strong class=\"example\">Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> functions = [x => 10 * x, x => 10 * x, x => 10 * x], x = 1\n<strong>Output:</strong> 1000\n<strong>Explanation:</strong>\nEvaluating from right to left ...\n10 * (1) = 10\n10 * (10) = 100\n10 * (100) = 1000\n</pre>\n\n<p><strong class=\"example\">Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> functions = [], x = 42\n<strong>Output:</strong> 42\n<strong>Explanation:</strong>\nThe composition of zero functions is the identity function</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code><font face=\"monospace\">-1000 <= x <= 1000</font></code></li>\n\t<li><code><font face=\"monospace\">0 <= functions.length <= 1000</font></code></li>\n\t<li>all functions accept and return a single integer</li>\n</ul>\n" ,
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"translatedTitle" : "复合函数" ,
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"translatedContent" : "<p>请你编写一个函数，它接收一个函数数组 <code>[f<sub>1</sub>, f<sub>2</sub>, f<sub>3</sub>，…， f<sub>n</sub>]</code> ，并返回一个新的函数 <code>fn</code> ，它是函数数组的 <strong>复合函数</strong> 。</p>\n\n<p><code>[f(x)， ， ： ： ： ,
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"code" : "/**\n * @param {Function[]} functions\n * @return {Function}\n */\nvar compose = function(functions) {\n \n\treturn function(x) {\n \n }\n};\n\n/**\n * const fn = compose([x => x + 1, x => 2 * x])\n * fn(4) // 9\n */" ,
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"code" : "type F = (x: number) => number;\n\nfunction compose(functions: F[]): F {\n \n\treturn function(x) {\n \n }\n};\n\n/**\n * const fn = compose([x => x + 1, x => 2 * x])\n * fn(4) // 9\n */" ,
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