DoorDash

Determine friend group sizes as friendships form among students.

Problem: Given n students (IDs 1 to n) and friendship queries, calculate group sizes.

Function Signature:

function sizeOfFriendGroups(n: number, queryType: string[], student: number[], student2: number[]): number

Example: Input:

• n = 4
• queryType = ["Friend", "Friend", "Total"]
• student1 = [1, 2, 1]
• student2 = [2, 3, 4]

Output: 4 Explanation: Groups {1,2,3} and {4}, sizes 3 + 1 = 4

Solution Strategy: Use Union-Find data structure for efficient group management.

Calculate airplane ticket costs based on airline, distance, and seating class.

Pricing Rules:

1. Seating Classes:

• Economy: No charge
• Premium: $25
• Business: $50 + $0.25/mile

2. Airlines:

• Delta: $0.50/mile + OperatingCost
• United: $0.75/mile + OperatingCost + $0.10/mile (Premium)
• Southwest: $1.00/mile
• LuigiAir: max($100, 2 * OperatingCost)

Example: Input:

United 150.0 Premium
Delta 60.0 Business
Southwest 1000.0 Economy
LuigiAir 50.0 Business

Output: [152.50, 95.00, 1000.00, 125.00]

Implementation: Use strategy pattern for flexible airline pricing functions.