PPractick

The problem

You're writing two helpers for a quiz app. The first receives the scores of everyone who took today's quiz and must report the sum and the highest score. Scores can be negative, because wrong answers cost points. The second receives the player's display name and must report how many vowels and how many consonants it contains, ignoring spaces, digits and punctuation, for a "name power" badge. Both are small, but they force you to use the two most basic containers correctly: indexing an array safely, starting a maximum from a real value, and treating a string as an array of characters.

Example: scores [3, 9, 2] → sum 14, max 9; name "Hello World" → 3 vowels, 7 consonants.

Function signature

pair<long long, int> sumAndMax(const vector<int>& scores);  // {sum, max}; scores is non-empty
pair<int, int> countVowelsConsonants(const string& name);   // {vowels, consonants}

Test cases

Input	Output	Explanation
scores [3, 9, 2]	sum 14, max 9	Basic case
scores [-5, -1, -7]	sum -13, max -1	Starting max at 0 would wrongly return 0
scores [4]	sum 4, max 4	Single element
name "Hello World"	vowels 3, consonants 7	The space is ignored
name "AEIOU xyz"	vowels 5, consonants 3	Uppercase vowels count too
name "R2-D2"	vowels 0, consonants 2	Digits and - are not letters
name ""	vowels 0, consonants 0	Empty string

(Confirm: the scores array has at least one element; only English letters count; 'y' is treated as a consonant.)

How interviewers phrase it

• "Find the sum and the maximum element of an array."
• "Count the vowels and consonants in a string."
• Theory questions in fresher rounds: "What is an array? How is it stored in memory? What's the difference between a C-style array and a vector? Are strings mutable?"

Clarifying questions to ask

1. Can the array be empty? Can it contain negative numbers?
2. How large can the values and the array get? (Decides whether the sum needs long long.)
3. For the string: should uppercase letters count? Should 'y' be a vowel? What about spaces, digits and punctuation?
4. Is the string plain ASCII, or can it contain Unicode characters?

Follow-ups to expect

1. "Why is array access O(1)?"
2. "What happens if you access a[n] in an array of size n?"
3. "C-style array vs vector?"
4. "Are strings mutable?"
5. "How do you convert a character to uppercase or check if it's a letter?"
6. "Why is s = s + c in a loop slow?"

Related questions

• Input Output Easy
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• If ElseIf Easy
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• While loops Easy

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