Cpp1_5.html

<article>
    <h1>C++ I: Page 5 - Loops: For & While</h1>

    <section>
        <h2>Automating Tasks with Repetition</h2>
        <p>Loops allow you to repeat actions. C++ supports <code>for</code>, <code>while</code>, <code>do-while</code>, and the modern range-based <code>for</code> loop (C++11 and later).</p>
        
        <h3>The Code implementation</h3>
        <pre><code class="language-cpp">/*
 * File: loops.cpp
 * Demonstration of various C++ looping mechanisms with control flow
 */
#include &lt;iostream&gt;
#include &lt;vector&gt;

using namespace std;

int main() {
    // 1. Traditional For Loop
    cout << "For loop (counting):" << endl;
    for (int i = 0; i < 3; i++) {
        cout << "  Iteration " << i << endl;
    }

    // 2. While Loop
    cout << "While loop (condition-based):" << endl;
    int j = 0;
    while (j < 3) {
        cout << "  Iteration " << j << endl;
        j++;
    }

    // 3. Do-While Loop (Always runs at least once)
    cout << "Do-While loop:" << endl;
    int k = 0;
    do {
        cout << "  Iteration " << k << endl;
        k++;
    } while (k < 0); // Still executes once

    // 4. Range-based For Loop (C++11)
    vector&lt;int&gt; nums = {10, 20, 30};
    cout << "Range-based loop:" << endl;
    for (int n : nums) {
        cout << "  Value: " << n << endl;
    }

    // 5. Advanced Loop Control: break/continue
    cout << "Loop control example:" << endl;
    for (int i = 0; i < 10; ++i) {
        if (i == 2) continue; // Skip 2
        if (i == 5) break;    // Exit at 5
        cout << "  Value: " << i << endl;
    }

    return 0;
}

/*
 * Loop Nuances:
 * 1. 'break' exits the loop immediately.
 * 2. 'continue' skips the rest of the current iteration and jumps to the next.
 * 3. Range-based loops are safer and more concise for containers, 
 *    preventing off-by-one errors.
 * 4. Infinite loops (e.g., while(true)) require a 'break' condition.
 * 5. Do-while guarantees at least one execution, useful for input validation.
 * 6. Always initialize your loop counter. Uninitialized variables lead to
 *    undefined behavior.
 * 7. When nested loops occur, 'break' only exits the innermost loop.
 */
        </code></pre>
        <div class="interactive-sim">
            <h3>Loop Simulator</h3>
            <button class="sim-button" onclick="
                const out = document.getElementById('sim-output-cpp1_5');
                out.innerHTML = 'for (int i=0; i&lt;3; i++) {<br>';
                setTimeout(() => out.innerHTML += '>> Iteration ' + 0 + '<br>', 400);
                setTimeout(() => out.innerHTML += '>> Iteration ' + 1 + '<br>', 800);
                setTimeout(() => out.innerHTML += '>> Iteration ' + 2 + '<br>', 1200);
                setTimeout(() => out.innerHTML += '}<br>', 1600);
            ">Run Simulation</button>
            <div id="sim-output-cpp1_5" class="sim-output"></div>
        </div>
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