Counting Failures in a Loop

1#include <iostream>
2#include <stdexcept>
3 
4int withdraw(int balance, int amount) {
5    if (amount > balance) {
6        throw std::runtime_error("insufficient funds");
7    }
8    return balance - amount;
9}
10 
11int main() {
12    int balance = 100;
13    int amounts[] = {30, 90, 50, 40};
14    int ok = 0;
15    int failed = 0;
16    for (int amount : amounts) {
17        try {
18            balance = withdraw(balance, amount);
19            ok++;
20            std::cout << "withdrew " << amount << ", balance " << balance << "\n";
21        } catch (const std::runtime_error& e) {
22            failed++;
23            std::cout << "refused " << amount << ": " << e.what() << "\n";
24        }
25    }
26    std::cout << ok << " ok, " << failed << " failed, balance " << balance << "\n";
27    return 0;
28}