findFirstIndex

Easy · Loops and Iterations · 3 test cases

Given an array and a target element, return the index of the first occurrence of the target element. If the element is not found, return -1.

Examples

findFirstIndex([1, 2, 3, 4, 3], 3) → 2
findFirstIndex(['a', 'b', 'c'], 'd') → -1
findFirstIndex([5, 10, 15, 20], 5) → 0

Starter code

function findFirstIndex(arr, target) {

}

Complexity of the optimal solution

Time O(n), space O(1). In the worst-case scenario, the function needs to iterate through the entire array to find the element or determine it's not present. This results in a time complexity proportional to the array size (n). The space used is constant.

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