JS Practice — Built-in Objects

Array.prototype.findLastIndex() — last long string index

📖 Usage Example

const words = ['hi', 'hello', 'hey']
words.findLastIndex(w => w.startsWith('h'))  // → 2

Use findLastIndex() to find the last position of a string matching a pattern.

Array.prototype.findLastIndex() — strings

findLastIndex() works just as well with strings and any other element type.

Challenge: Implement lastLongIndex(strs, minLen) that returns the index of the last string with length >= minLen.

lastLongIndex(['hi', 'hello', 'world', 'ok'], 5) // → 2
lastLongIndex(['a', 'b', 'c'], 3)                 // → -1

💡 Hints (2)