Currency Converter in C++

#include <iostream>
#include <map>
#include <iomanip>

using namespace std;

// Function to convert currency
double convertCurrency(double amount, double exchangeRate) {
    return amount * exchangeRate;
}

int main() {
    // Exchange rates (example rates, you should use actual rates)
    map<string, double> exchangeRates;
    exchangeRates["USD"] = 1.0;
    exchangeRates["EUR"] = 0.85;
    exchangeRates["GBP"] = 0.75;

    cout << "Currency Converter" << endl;

    // Input currency and amount
    string fromCurrency, toCurrency;
    double amount;

    cout << "Enter the source currency (e.g., USD): ";
    cin >> fromCurrency;

    if (exchangeRates.find(fromCurrency) == exchangeRates.end()) {
        cout << "Invalid source currency." << endl;
        return 1;
    }

    cout << "Enter the target currency (e.g., EUR): ";
    cin >> toCurrency;

    if (exchangeRates.find(toCurrency) == exchangeRates.end()) {
        cout << "Invalid target currency." << endl;
        return 1;
    }

    cout << "Enter the amount to convert: ";
    cin >> amount;

    // Perform the currency conversion
    double convertedAmount = convertCurrency(amount, exchangeRates[toCurrency] / exchangeRates[fromCurrency]);

    // Display the result
    cout << fixed << setprecision(2);
    cout << amount << " " << fromCurrency << " = " << convertedAmount << " " << toCurrency << endl;

    return 0;
}