[Solved] Identify the error in this Order class method:class Order { Map items = new HashMap(); void add_item(String name, int qty) { items.put(name, qty); } } | LLD

LLD - Design — Food Delivery System

Identify the error in this Order class method:

class Order {
  Map items = new HashMap<>();
  void add_item(String name, int qty) {
    items.put(name, qty);
  }
}

ANo error, code is correct

BMap should use List instead of Integer

CIt overwrites quantity instead of adding

DMethod name should be addItem

Step-by-Step Solution

Solution:

Step 1: Understand add_item behavior
Using put replaces existing quantity instead of adding to it.
Step 2: Identify correct approach
Should check if item exists and add qty to existing value.
Final Answer:
It overwrites quantity instead of adding -> Option C
Quick Check:
put() replaces values, not accumulates [OK]

Quick Trick: put() replaces; use get + add for quantities [OK]

Common Mistakes:

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