循环读取dat文件不正确

Question

早上好，

我有一个读取dat文件的循环，但该循环读取的数据不正确。我的dat文件包含以下数据

46780976 3750.40
W 250.00
D 1200.00
W 75.00
W 375.00
D 1200.00
I 5.50
W 400.00
W 600.00
D 450.50
W 35.65

输出应为

Account number: 46780976
Opening balance: R3750.40

Transaction    Amount    Balance Bank costs
Withdrawal     250.00    4000.00
Deposit       1200.00Ct  2800.00
Withdrawal        75.00  2725.00
Withdrawal      1375.00   1350.00
Deposit        1200.00Ct 1550.00
Interest         5.50    1555.50
Withdrawal      400.00   1155.50
Withdrawal      600.00   555.50     25.00
Deposit         450.00Ct 1005.50
Withdrawal       35.65    969.85
Banking costs    25.00    969.60

Closing balance: R969.60

我得到了以下信息

Account number : 46780976

Opening Balance : R 3750.4

Transaction        Amount          Balance         Bank Costs


Withdrawal            250            3500.4
Deposit            0 Ct            3500.4
Interest              0            3500.4

Withdrawal            250            3225.4
Deposit            1200 Ct            4425.4
Interest              0            4425.4

Withdrawal            75            4325.4
Deposit            1200 Ct            5525.4
Interest              0            5525.4

Withdrawal            375            5125.4
Deposit            1200 Ct            6325.4
Interest              0            6325.4

Withdrawal            375            5925.4
Deposit            1200 Ct            7125.4
Interest              0            7125.4

Withdrawal            375            6725.4
Deposit            1200 Ct            7925.4
Interest              5.5            7930.9

Withdrawal            400            7505.9
Deposit            1200 Ct            8705.9
Interest              5.5            8711.4

Withdrawal            600            8086.4
Deposit            1200 Ct            9286.4
Interest              5.5            9291.9

Withdrawal            600            8666.9
Deposit            450.5 Ct            9117.4
Interest              5.5            9122.9

Withdrawal            35.65            9062.25
Deposit            450.5 Ct            9512.75
Interest              5.5            9518.25

Withdrawal            35.65            9457.6
Deposit            450.5 Ct            9908.1
Interest              5.5            9913.6
Bank Costs           25            9888.6            25


Closing Balance : R 9888.6
Press any key to continue . . .

我的代码：

do { 
   in_stream >> letter;

if (letter == 'W')

    in_stream >> withdrawal;
    openBalance -= withdrawal;
    cout << "\nWithdrawal" << "            "<< withdrawal << "            " << openBalance << endl;
    out_stream << withdrawal;

if (letter == 'D')

    in_stream >> deposit;
    openBalance += deposit;
    cout << "Deposit" <<"            "<< deposit <<" Ct" <<"            " << openBalance << endl;
    out_stream << deposit;


if (letter == 'I')

    in_stream >> interest;
    openBalance += interest;
    cout << "Interest" <<"              "<< interest <<"            " << openBalance << endl;
    out_stream << interest;

 if (openBalance < 1000)
     cout << "Bank Costs" <<"           "<< bankCost <<"            " << openBalance <<"            " << bankCost << endl;
    openBalance -= bankCost;
    out_stream << bankCost;

} while(!in_stream.eof());

请给我指出正确的方向

谢谢

Answer 1

您的第一个问题是if代码块。在C++中，'if‘语句会立即影响后面的代码行或block.so...

if( Xxx )
    thisHappensOnlyIfXxxIsTrue
thisAlwaysHappens

if( Xxx )
    thisHappensOnlyIfXxxIsTrue
    thisAlwaysHappens  // even though it's indented


if( Xxx ) {
    thisHappensOnlyIfXxxIsTrue
    thisDependsOnXxxToo
}
thisAlwaysHappens

下一个问题是，您不是在每次循环重新启动时都清除变量。您需要插入一个

do {
   deposit = 0;
   interest = 0;
   withdrawal = 0;

在循环开始(或结束)时，确保不会重复使用上一次循环迭代中的值。

Answer 2

因为第一行是：

46780976 3750.40

这一行将通过，但没有预期的内容：

in_stream >> letter;

当然，假设letter的类型是char

编辑

// You need to read in the initial values here

do { 
   in_stream >> letter;

if (letter == 'W')
{
    in_stream >> withdrawal;
    openBalance -= withdrawal;
    cout << "\nWithdrawal" << "            "<< withdrawal << "            " << openBalance << endl;
    out_stream << withdrawal;
}

if (letter == 'D')
{
    in_stream >> deposit;
    openBalance += deposit;
    cout << "Deposit" <<"            "<< deposit <<" Ct" <<"            " << openBalance << endl;
    out_stream << deposit;
}

if (letter == 'I')
{

    in_stream >> interest;
    openBalance += interest;
    cout << "Interest" <<"              "<< interest <<"            " << openBalance << endl;
    out_stream << interest;
 }

 if (openBalance < 1000)
 {
     cout << "Bank Costs" <<"           "<< bankCost <<"            " << openBalance <<"            " << bankCost << endl;
    openBalance -= bankCost;
    out_stream << bankCost;
  }

} while(!in_stream.eof());