Your free access ends in 7 days — and you haven’t tried it yet. Watch one algorithm run, start to finish. It takes about two minutes.

Problem

Contains Duplicate

Any value appear twice?

Given an integer array, return true if any value appears at least twice, and false if every element is distinct.

Asked atAmazonAppleGoogle

Brute force

time O(n²)space O(1)

step 1 / 16

[0][1][2][3][4]

Brute force


▸
1for i ← 0 to n − 2:
2    for j ← i + 1 to n − 1:
3        if arr[i] == arr[j]:
4            return true
5return false

state

—

line 1Return true if any value appears at least twice.