Files
UoL/CM2005 Object Oriented Programming/Topic 2/2.3.11/main.cpp
2021-05-20 15:59:38 -05:00

90 lines
2.3 KiB
C++

#include <iostream>
#include <string>
#include <vector>
enum class OrderBookType
{
bid,
ask
};
class OrderBookEntry
{
public:
OrderBookEntry
(
double price,
double amount,
std::string timestamp,
std::string product,
OrderBookType orderType
)
: price{price},
amount(amount),
timestamp(timestamp),
product(product),
orderType(orderType)
// can use parenthesis or curly braces
{
}
double price;
double amount;
std::string timestamp;
std::string product;
OrderBookType orderType;
};
int main()
{
std::vector<OrderBookEntry> orders;
// OrderBookEntry order1{ 10000,
// 0.002,
// "2020/03/17 17:01:24.884492",
// "BTC/USDT",
// OrderBookType::bid};
orders.push_back( OrderBookEntry{
10000,
0.002,
"2020/03/17 17:01:24.884492",
"BTC/USDT",
OrderBookType::bid});
orders.push_back( OrderBookEntry{
50000,
0.002,
"2020/03/17 17:01:24.884492",
"BTC/USDT",
OrderBookType::bid});
// Version 1
std::cout << "Version 1" << std::endl;
for(OrderBookEntry order : orders) //this create a copy of the members of orders and assigns it to 'order'
{
std::cout << "The price is " << order.price << std::endl;
}
std::cout << "---new line---" << std::endl;
for(OrderBookEntry &order : orders) //this doesn't crate a copy
{
std::cout << "The price is " << order.price << std::endl;
}
// Version 2
std::cout << "Version 2" << std::endl;
for(unsigned int i=0; i<orders.size(); ++i) //thid doesn't create a copy, ++i increments on the same variable
{
std::cout << "The price is " << orders[i].price << std::endl;
}
//version 3
std::cout << "Version 3" << std::endl;
for(unsigned int i=0; i<orders.size(); ++i) //thid doesn't create a copy, ++i increments on the same variable
{
std::cout << "The price is " << orders.at(i).price << std::endl;
}
}