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Codeforces

Easy

Arrays

Sorting

IQ test

Find the position of the number whose parity differs from the rest.

Acceptance 0%

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Problem Statement

Problem

You are given an array of integers. All numbers are of the same parity except one: either exactly one number is even while all others are odd, or exactly one number is odd while all others are even.

Your task is to determine the 1-based index of that different number.

Input Format

The first line contains an integer $n$ — the number of elements.
The second line contains $n$ integers.

Output Format

Print one integer: the 1-based position of the element whose parity is different from the others.

Constraints

$3 \le n$
Exactly one element has a different parity than all others.
The answer is guaranteed to exist.

Hints

Check the parity of the first three elements to identify the majority parity.
Then scan once to find the outlier.

Input Format

Integer $n$
Array of $n$ integers

Output Format

A single integer: the 1-based index of the outlier

Constraints

Exactly one element has different parity than the rest
The answer is guaranteed to exist

Examples

Sample cases returned by the problem API.

Example 1

Input

5
2 4 7 8 10

Output

Explanation

All numbers are even except 7, which is at position 3.

Example 2

Input

3
9 2 1

Output

Explanation

Only 2 is even; the others are odd.

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