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Practice Check if Array is Good

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

Easy#2784
LeetCode Problem

Check if Array is Good

ArrayHash TableSorting

Problem Statement

You are given an integer array nums. We consider an array good if it is a permutation of an array base[n]. base[n] = [1, 2, ..., n - 1, n, n] (in other words, it is an array of length n + 1 which contains 1 to n - 1 exactly once, plus two occurrences of n). For example, base[1] = [1, 1] and base[3] = [1, 2, 3, 3]. Return true if the given array is good, otherwise return false. Note: A permutation of integers represents an arrangement of these numbers.

Source: Check if Array is Good on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input
nums = [2, 1, 3]
Output
false

# Example 2

Input
nums = [1, 3, 3, 2]
Output
true

# Example 3

Input
nums = [1, 1]
Output
true

# Example 4

Input
nums = [3, 4, 4, 1, 2, 1]
Output
false

Constraints

1 <= nums.length <= 100
1 <= num[i] <= 200

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