Practice RLE Iterator

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Medium#900

LeetCode Problem

RLE Iterator

Array Design Counting Iterator

Problem Statement

RLEIterator(encoding) receives alternating repetition counts and values. next(n) consumes the next n decoded entries and returns the last consumed value. If fewer than n entries remain, consume the remainder and return -1. Zero-length runs contribute no entries. Practice approach: Keep a run pointer and remaining count rather than expanding the sequence, because counts may reach 10^9. Skip exhausted runs while subtracting their sizes from n. A request ending exactly at a run boundary still returns that run's value. Across calls, each run is passed at most once.

Source: RLE Iterator on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input

["RLEIterator","next","next","next","next"]
[[[2,4,0,9,3,7]],[2],[1],[3],[1]]

Output

[null,4,7,-1,-1]

Explanation

The decoded sequence is [4,4,7,7,7]. The third request exceeds the remaining two entries and exhausts the iterator.

Constraints

2 <= encoding.length <= 1000

encoding.length is even.

0 <= encoding[i] <= 10^9

1 <= n <= 10^9

At most 1000 next calls.

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