在C++中向數組結構添加元素

Question

即時在C++上做一項任務，我堅持要如何使用用戶定義的numShares和pricePerShare將新事務添加到我的工作中。

我有一個交易結構，看起來像這樣：

struct Transaction 
{ 
string stockSymbol;  // String containing the stock symbol, e.g. "AAPL" 
string buyerName;  // String containing the buyer's name e.g. "Mr Brown" 
int buyerAccount;  // Integer containing an eight digit account code 
int numShares;   // Integer containing the number of sold shares 
int pricePerShare;  // Integer containing the buy price per share 
}; 

這是buildTransaction類：

static Transaction* buildTransactions(int numTransactions) 
{ 
    int maxShareVolume = 100000; 
    int maxSharePrice = 1000; 

    Transaction *transactions = new Transaction[numTransactions]; 

     for(int idx = 0; idx < numTransactions; idx++) 
     { 
      transactions[idx].stockSymbol = pickRandomStockSymbol(); 

      std::string buyerName = pickRandomBuyer(); 
      transactions[idx].buyerName = buyerName; 
      transactions[idx].buyerAccount = lookupBuyerAccount(buyerName); 

      transactions[idx].numShares = 1 + rand() % maxShareVolume; 
      transactions[idx].pricePerShare = 1 + rand() % maxSharePrice;  
     } 

     return transactions; 
    } 

如何將我用它來使用這個數據添加到交易數組：

void Analyser::addTransactions(Transaction* transactions, int numTransactions) 

我會從這個假設，我真的需要作爲用戶輸入wo它是股份數量和每股價格，但其他信息自動填充，從數組中選擇。

Answer 1

的buildTransactions代替使用陣列，則應使用矢量..會這樣寫：

：通過編輯此buildTransactions功能

std::vector<Transaction> buildTransactions(int numTransactions) 
{ 
    int maxShareVolume = 100000; 
    int maxSharePrice = 1000; 
    std::vector<Transaction> transactions; 

    for(int idx = 0; idx < numTransactions; idx++) 
    { 
     Transaction t; 
     t.stockSymbol = pickRandomStockSymbol(); 
     std::string buyerName = pickRandomBuyer(); 
     t.buyerName = buyerName; 
     t.buyerAccount = lookupBuyerAccount(buyerName); 
     t.numShares = 1 + rand() % maxShareVolume; 
     t.pricePerShare = 1 + rand() % maxSharePrice; 

     transactions.push_back(t); 
    } 

    return transactions; 
} 

，您可以輕鬆地這樣做是爲了您的addTransactions功能添加更多數據

希望能對你有所幫助:)

Answer 2

可以得到的股量，並且在addTransactions每股價格作爲輸入在一個循環中（）方法如下所示：

for(int idx = 0; idx < numTransactions; idx++) 
    { 
     transactions[idx].stockSymbol = pickRandomStockSymbol(); 

     std::string buyerName = pickRandomBuyer(); 
     transactions[idx].buyerName = buyerName; 
     transactions[idx].buyerAccount = lookupBuyerAccount(buyerName); 

     ctd::cout<<"Enter number of shares for transaction "<<idx+1<<std::endl; 
     std::cin>>transactions[idx].numShares; 
     ctd::cout<<"Enter price per share for transaction "<<idx+1<<std::endl; 
     std::cin>>transactions[idx].pricePerShare;  
    }