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Design Parking System

EasyArrays

Track parking spots of three sizes and admit cars while space remains.

Open problem
Constraints
  • 0 <= big, medium, small <= 1000
  • carType in {1, 2, 3}

Three counters

Time O(1) per carSpace O(1)

Store one remaining-count per size. addCar checks the counter for the car's type: if it is positive, decrement it and return true; otherwise return false. Constant time per car.

Key terms
counter:
An integer tracking how many spots of a given size are still free.
bool addCar(int carType) {
    if (slots[carType] > 0) { slots[carType]--; return true; }
    return false;
}
Step by step
  1. Store counts indexed by type: slots[1]=big, slots[2]=medium, slots[3]=small.
  2. addCar(type): if slots[type] > 0, decrement and return true.
  3. Otherwise return false (no spot of that size).