Question

我的函数包含一个字符串和整数，但在运行时我得到错误：

error: could not convert 'balance' from 'int' to 'std::string {aka std::basic_string<char>}'

我想要完成的是编写一个程序，询问您是否要“存款”或“退出”。然后，程序将提示输入一个美元金额（整数值）。编写'update_balance'函数以适当修改余额。如果命令是“存款”，则您的功能应将美元金额添加到当前余额中;如果命令是“撤销”，则您的函数应从当前余额中减去美元金额。

执行命令后返回新的余额。

我目前的代码是：

#include <iostream>
#include <string>
using namespace std;
//************************FUNCTION TO BE FIXED************************
void update_balance(string command, int dollars, int balance)
{
    if (command == "withdraw")
    {
        balance = balance - dollars;
    }
    else
    {
        balance = balance + dollars;
    }
}
//************************FUNCTION TO BE FIXED************************

int main()
{
    //the amount of money in your account
    int balance = 0;

    // Command that will tell your function what to do
    string command;
    cin >> command;

    // number of dollars you would like to deposit or withdraw
    int dollars = 0;
    cin >> dollars;

    balance = update_balance(balance, dollars, command);

    // Prints out the balance
    cout << balance << endl;

    return 0;
}

Answer 1

我发现了一些错误。这是我的建议。设置余额= 500而不是0。改变

void update_balance(string command, int dollars, int balance)

到

int update_balance(int balance, int dollars, string command)

在if-else循环后添加一行。

return balance;

添加int balancen。

更改

balance = update_balance(balance, dollars, command);

到

balancen = update_balance(balance, dollars, command);

Answer 2

我建议通过引用或指针传递参数，如下所示：

#include <iostream>
#include <string>
using namespace std;

void update_balance(string command, int& balance, int dollars)
{
    if (command == "withdraw")
        balance -= dollars;
    else
        balance += dollars;
}

int main()
{
    //the amount of money in your account
    int balance = 0;

    // Command that will tell your function what to do
    string command;
    cin >> command;

    // number of dollars you would like to deposit or withdraw
    int dollars = 0;
    cin >> dollars;

    update_balance(command, balance, dollars);

    // Prints out the balance
    cout << balance << endl;

    return 0;
}

返回银行帐户余额的功能

2 个答案: