Ответ:

#include <iostream>

#include <map>

#include <string>

using namespace std;

int main() {

 // Task 1: Input validation

 int lower_limit, upper_limit, input_num;

 cout << "Enter lower limit: ";

 cin >> lower_limit;

 cout << "Enter upper limit: ";

 cin >> upper_limit;

 while (true) {

   cout << "Enter a number within the range [" << lower_limit << "," << upper_limit << "]: ";

   cin >> input_num;

   if (input_num >= lower_limit && input_num <= upper_limit) break;

   cout << "The number is outside the range. Please try again." << endl;

 }

 // Task 2: Cash register simulation

 map<string, int> products = {{"Product 1", 100}, {"Product 2", 200}, {"Product 3", 300}, {"Product 4", 400}};

 int total_purchase_amount = 0;

 int max_inventory = 10;

 string product_name;

 int product_quantity;

 while (true) {

   cout << "Enter product name (or 'quit' to exit): ";

   cin >> product_name;

   if (product_name == "quit") break;

   auto it = products.find(product_name);

   if (it == products.end()) {

     cout << "Invalid product name. Please try again." << endl;

     continue;

   }

   cout << "Enter quantity: ";

   cin >> product_quantity;

   if (product_quantity <= 0 || product_quantity > max_inventory) {

     cout << "Invalid quantity. Please try again." << endl;

     continue;

   }

   total_purchase_amount += product_quantity * it->second;

   max_inventory -= product_quantity;

   cout << "Current total purchase amount: " << total_purchase_amount << endl;

 }

 cout << "Total purchase amount: " << total_purchase_amount << endl;

 return 0;

}

Объяснение: