c++ - 未定义的函数引用 (c++)

Question

我在问之前搜索了这个问题，我发现每个人都在使用 .h 文件来实现他们的功能，而我的老师教我们将 main 和功能放在一个文件中。

我只是想弄清楚为什么它是未定义的。我知道此代码中可能还存在其他问题，但我真的无法弄清楚我做错了什么。

这是我的代码:

#include <iostream>
#include <iomanip>

using namespace std;

void start();
void process();
void check();
void deposit();

const float dserv = 0.10;
const float cserv = 0.15;
const float fiveserv = 5.0;
const float oserv = 10.0;

int main()
{
float balance;
float amount;
bool fivehun;
bool endcheck;
float servcharge;
float servchargetotal;
char type;

start();
while(endcheck != true)
{process();}
cout<<"Current balance: $"<<balance<<endl;
cout<<"Total service charges: $"<<servchargetotal<<endl;
cout<<"Final balance: $"<<
system("pause");
return 0;
}

void start(float balance)
{
    balance = 0;
    cout<<fixed<<showpoint<<setprecision(2);
    cout<<"Transactions will take the form of a letter followed by a dollar ";
    cout<<"amount. Valid letters are “C” for a check, “D” for a deposit, and";
    cout<<"“E” for the ending transaction (use zero on this transaction).";
    cout<<"Press <Enter> after each line of input";
    cout<<"Enter the beginning balance:"<<endl;
    cin>>balance;
}

void process(float balance, float amount, char type, bool endcheck)
{
    cout<<"Enter a transaction:"<<endl;
    cin>>type>>amount;
    if (type = "C"||"c")
    {check();
    endcheck = false;}
    else if(type = "D"||"d")
    {deposit();
    endcheck = false;}
    else if(type= "E"||"e")
    {endcheck = true;}
}

void check(float balance, float amount, bool fivehun, float servcharge, float& servchargetotal)
{
    balance = balance - amount;
    servcharge = cserv;
    if (balance<500.00)
    {fivehun = true;}
    else
    {fivehun = false;}

    cout<<"Transaction: Check in amount of $"<<amount<<endl;
    cout<<"Current balance: $"<<balance<<endl;
    cout<<"Service charge: Check - $"<<cserv<<endl;
    if (fivehun == true)
    {cout<<"Service charge: Below $500 - $"<<fiveserv<<endl;
     servcharge = (fiveserv+servcharge);}
    cout<<"Total service charges: $"<<servcharge<<endl;
    servchargetotal = servchargetotal + servcharge;
}

void deposit(float balance, float amount, bool fivehun, float servcharge, float& servchargetotal)
{
    balance = balance + amount;
    servcharge = dserv;
    if (balance<500.00)
    {fivehun = true;}
    else
    {fivehun = false;}

    cout<<"Transaction: Deposit in amount of $"<<amount<<endl;
    cout<<"Current balance: $"<<balance<<endl;
    cout<<"Service charge: Check - $"<<cserv<<endl;
    if (fivehun == true)
    {cout<<"Service charge: Below $500 - $"<<fiveserv<<endl;
     servcharge = (fiveserv+cserv);}
    cout<<"Total service charges: $"<<servcharge<<endl;
    servchargetotal = servchargetotal + servcharge;
}

如果有任何我可以详细说明的地方，我会尽我所能进行编辑/评论。

Answer 1

检查你的 start 功能，如 M.M.你应该得到这样的东西:

float start() {
    // ...
    float balance;
    cin >> balance;
    return balance;
}


int main() {
    float n;
    n = start();
    // ...
    return 0;
}

并逐步检查所有函数，因为您在下一个 process 函数中遇到问题:in if statement must be comparison operator if (type == "C"|| type == "c") 而不是赋值 type = "C"||"c"。