MediumType Coercion💻 Output Question

parseInt stops at first invalid character

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Hint

parseInt stops at the first non-parseable character. Always specify the radix to avoid ambiguity.

What does this output?

console.log(parseInt('10px'));
console.log(parseInt('0x1F'));
console.log(parseInt('10', 2));
console.log(parseInt('hello'));

Correct Output

10
31
2
NaN

Why this output?

Explanation: "10px"→10 (stops at p). "0x1F" is hex=31. Base 2: "10"=2. "hello"→NaN (no valid digits).

Key Insight: parseInt stops at the first non-parseable character. Always specify the radix to avoid ambiguity.

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