Printing the Inventory Report

Part of the Logic & Flow section of Coddy's C++ journey — lesson 34 of 56.

Challenge

Easy

Complete your inventory tracking system by implementing a comprehensive inventory report feature. This final lesson demonstrates how to iterate through an entire map and present all stored data in a clean, organized format.

Start with the following inventory:

map<string, int> inventory = {
    {"apples", 50},
    {"bananas", 30},
    {"oranges", 25},
    {"grapes", 40},
    {"strawberries", 15}
};

Your program should:

Generate a complete inventory report that displays all items and their current quantities
Calculate and display the total number of different items in the inventory
Calculate and display the total quantity of all items combined
Identify and display the item with the highest quantity
Identify and display the item with the lowest quantity

Use the following exact output format:

Inventory report header:

===== INVENTORY REPORT =====

All items (in alphabetical order):

apples: 50
bananas: 30
grapes: 40
oranges: 25
strawberries: 15

Summary statistics:

===== SUMMARY =====
Total items: 5
Total quantity: 160
Highest stock: apples (50)
Lowest stock: strawberries (15)

Use a range-based for loop to iterate through the entire inventory map. For each key-value pair, access the item name with pair.first and the quantity with pair.second. The map automatically maintains alphabetical order when iterating, so no additional sorting is needed.

To find the lowest quantity item, initialize your lowestQuantity variable to INT_MAX (the largest possible integer value, available after including <climits> or <iostream>). This ensures the very first item's quantity will always be less than the starting value, so the comparison works correctly regardless of the actual quantities in the inventory.

Try it yourself

#include <iostream>
#include <map>
#include <string>
using namespace std;

int main() {
    // Initialize inventory with existing items
    map<string, int> inventory;
    inventory["apples"] = 50;
    inventory["bananas"] = 30;
    inventory["oranges"] = 25;
    
    int n;
    cin >> n;
    
    for (int i = 0; i < n; i++) {
        string itemName;
        int quantity;
        cin >> itemName >> quantity;
        
        if (inventory.count(itemName) == 0) {
            cout << "Error: " << itemName << " not found in inventory" << endl;
        } else if (inventory[itemName] < quantity) {
            cout << "Error: Cannot remove " << quantity << " " << itemName << ". Only " << inventory[itemName] << " in stock" << endl;
        } else {
            inventory[itemName] -= quantity;
            cout << "Removed " << quantity << " " << itemName << ". New total: " << inventory[itemName] << endl;
        }
    }
    
    cout << "Final Inventory:" << endl;
    for (auto& item : inventory) {
        cout << item.first << ": " << item.second << endl;
    }
    
    return 0;
}