开发需求：从100倒数至指定正整数N并分离奇偶数字

Hey there! Let's fix up that code to meet your requirement of counting down from 100 to a user-input positive integer N, splitting even and odd numbers into separate lines. Here's a practical implementation that addresses your needs clearly:

<div id="results"></div>
<script>
function countDownAndSeparate() {
    // Get user input first
    let userInput = prompt("Please enter a positive integer N (≤ 100):", "");
    if (!userInput) return; // Exit if user cancels the prompt
    
    // Convert input to integer and validate it
    const N = parseInt(userInput);
    if (isNaN(N) || N <= 0 || N > 100) {
        alert("Whoops! Please enter a valid positive integer that's no greater than 100.");
        return;
    }
    
    // Initialize arrays to hold our even and odd numbers
    const evenNumbers = [];
    const oddNumbers = [];
    
    // Loop from 100 all the way down to N (inclusive)
    for (let i = 100; i >= N; i--) {
        if (i % 2 === 0) {
            evenNumbers.push(i); // Add to evens if divisible by 2
        } else {
            oddNumbers.push(i); // Add to odds otherwise
        }
    }
    
    // Turn our arrays into space-separated strings for display
    const evenString = evenNumbers.join(" ");
    const oddString = oddNumbers.join(" ");
    
    // Populate the results in the DOM
    const resultsContainer = document.getElementById("results");
    resultsContainer.innerHTML = `
        <p><strong>Even numbers:</strong> ${evenString}</p>
        <p><strong>Odd numbers:</strong> ${oddString}</p>
    `;
}

// Run the function when the page loads (you could also attach this to a button click!)
countDownAndSeparate();
</script>

• Input Validation: Makes sure the user enters a valid number (no empty values, non-numeric text, or numbers outside the 1-100 range) to avoid errors.
• Categorization: Loops from 100 down to your input N, sorting each number into even or odd groups using a simple modulo check.
• Clean Output: Displays the results in a readable format with clear labels so you can easily tell which line is evens vs odds.

I noticed your provided test cases seem to have a small discrepancy (e.g., inputting 10 shows results stopping at 92/91 instead of 10). Assuming that was a typo, here's what you'd get with correct inputs matching the test case patterns:

• If you input 90, you'll get evens: 100 98 96 94 92 90 and odds: 99 97 95 93 91
• If you input 96, you'll get evens: 100 98 96 and odds: 99 97

If you actually wanted to count a fixed number of steps instead of stopping at N, we could adjust the loop to run (100 - N) times instead of going down to N—but based on your initial description, stopping at N is the right approach.

内容的提问来源于stack exchange，提问作者David Smith