Solution

Method 1 – Closure (Stateful Function)

Intuition

The key idea is to use a closure to capture the current value of the counter. Each time the returned function is called, it increments and returns the value, maintaining state between calls.

Approach

Define a function createCounter that takes an integer n.
Inside, define and return a function that:
- Returns the current value.
- Increments the value for the next call.
The closure ensures the value persists across calls.

Code

[{"language":"JavaScript","code":"function createCounter(n) {\n    let ans = n;\n    return function() {\n        return ans++;\n    };\n}","lang":"javascript","html":"<pre class=\"shiki shiki-themes github-light github-dark\" style=\"background-color:#fff;--shiki-dark-bg:#24292e;color:#24292e;--shiki-dark:#e1e4e8\" tabindex=\"0\"><code><span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">function</span><span style=\"color:#6F42C1;--shiki-dark:#B392F0\"> createCounter</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">(</span><span style=\"color:#E36209;--shiki-dark:#FFAB70\">n</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">) {</span></span>\n<span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">    let</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\"> ans </span><span style=\"color:#D73A49;--shiki-dark:#F97583\">=</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\"> n;</span></span>\n<span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">    return</span><span style=\"color:#D73A49;--shiki-dark:#F97583\"> function</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">() {</span></span>\n<span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">        return</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\"> ans</span><span style=\"color:#D73A49;--shiki-dark:#F97583\">++</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">;</span></span>\n<span class=\"line\"><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">    };</span></span>\n<span class=\"line\"><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">}</span></span></code></pre>"},{"language":"TypeScript","code":"function createCounter(n: number): () => number {\n    let ans = n;\n    return function(): number {\n        return ans++;\n    };\n}","lang":"typescript","html":"<pre class=\"shiki shiki-themes github-light github-dark\" style=\"background-color:#fff;--shiki-dark-bg:#24292e;color:#24292e;--shiki-dark:#e1e4e8\" tabindex=\"0\"><code><span class=\"line\"><span style=\"color:#D73A49;--shiki-dark:#F97583\">function</span><span style=\"color:#6F42C1;--shiki-dark:#B392F0\"> createCounter</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">(</span><span style=\"color:#E36209;--shiki-dark:#FFAB70\">n</span><span style=\"color:#D73A49;--shiki-dark:#F97583\">:</span><span style=\"color:#005CC5;--shiki-dark:#79B8FF\"> number</span><span style=\"color:#24292E;--shiki-dark:#E1E4E8\">)</span><span style=\"color:#D73A49;--shiki-dark:#F97583\">:</span><span style=\"color

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