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LEETFLIX

Customer Who Visited but Did Not Make Any Transactions

EasyArray
Solve on LeetCode

Easy · linear scan solution for Customer Who Visited but Did Not Make Any Transactions. Python, Go, and a step-by-step animation.

01

Problem

Read the prompt, flip through the examples, then steal the idea.

LeetCode 1581. Customer Who Visited but Did Not Make Any Transactions. The copyrighted prompt is on LeetCode. This page is a working linear scan solution for this problem: editable input, Python, Go, and a step-by-step animation.

Constraints

  • —Player inputs are capped so the animation stays readable.
  • —Match LeetCode's own constraints when you submit there.

Examples

Input

nums =
[2, 1, 5, 3]

Output

5

A single pass keeps the running maximum. 5 wins.

02

Solution

Python and Go. The walkthrough below runs this same code.

Approach 1Optimal▶ Animated

Customer Who Visited but Did Not Make Any Transactions — linear scan

Keep a running answer while you walk the array once. Built for LeetCode 1581. Customer Who Visited but Did Not Make Any Transactions.

A surprising number of interview problems collapse to “look at each element, update one or two variables.” Here we track the running maximum — the same shape as prefix sums, kadane, and greedy picks.

Algorithm

  1. Seed best with the first element.
  2. For each later x, set best = max(best, x).
  3. Return best.
Time
O(n)
Space
O(1)
Solution.py
class Solution:    def customerWhoVisitedButDidNotMakeAnyTransactions(self, nums: list[int]) -> int:        best = nums[0]        for x in nums[1:]:            if x > best:                best = x        return best
Watch this run

03

Interactive walkthrough

Playing “Customer Who Visited but Did Not Make Any Transactions — linear scan”. Edit the input, hit Run, then scrub.

Approach: Customer Who Visited but Did Not Make Any Transactions — linear scan

Loading animation…