Question

我一直在为C ++类开发抵押计算器。但是，我被困住了。

我从Nerdwallet获得了以下公式，并尝试在我的程序中实现它：

M = P [i（1 + i）^ n] / [（1 + i）^ n – 1]

M =抵押付款

P =校长

i =兴趣

n =付款次数

这是我当前正在使用的代码。

#include <iostream>
#include <cstdlib>
#include <cmath>

using namespace std;

int main(int argc, char** argv) 
{
    int years, homePrice, creditScore, totalPayments;
    float rate, mortgageTotal, monthlyPayment;
    cout << "What is the price of the home that you are looking to mortgage?\n";
    cin >> homePrice; //Assigns the variable homePrice to a value

    cout << "What is your credit score?\n";
    cin >> creditScore; //Assigns the creditScore variable a value
    cout << "Would you prefer a 15 year or 30 year mortgage? Please type 15 or 30.\n";
    cin >> years;

if ( years = 15 ) //If input is 15 year it will go down this logical path
    {
        if (creditScore >=760) //If their credit rating is equal to or more than 760, their rate will be .043 also nested if.
            { 
                rate = .043;
                cout << "Your interest rate is 4.3%\n";
            }
        else if (creditScore >= 700) //If their credit rating is equal to or more than 700, their rate will be .0455
            {
                rate = .0455;
                cout << "Your interest rate is 4.55%\n";
            }
        else if (creditScore >= 660) //If their credit rating is equal to or more than 660, their rate will be .048
            {
                rate = .048;
                cout << "Your interest rate is 4.8%\n";
            }
        else if (creditScore >= 620) //If their credit rating is equal to or more than 620, their rate will be .058
            {
                rate = .058;
                cout << "Your interest rate is 5.8%\n";
            }
        else if (creditScore >= 580) //If their credit rating is equal to or more than 580, their rate will be .0655
            {
                rate = .0655;
                cout << "Your interest rate is 6.55%\n";
            }
        else if (creditScore >= 500) //If their credit rating is equal to or more than 500, their rate will be .083
            {
                rate = .083;
                cout << "Your interest rate is 8.3%\n";
            }
    }
else if ( years=30 ) 
    {
        if (creditScore >= 760)
            {
                rate=.043;
                cout <<"Your interest rate is 4.3%\n";
            }
        else if (creditScore >= 700)
            {
                rate=.0455;
                cout << "Your interest rate is 4.55%\n";
            }
        else if (creditScore >= 660)
            {
                rate=.048;
                cout << "Your interest rate is 4.8%\n";
            }
        else if (creditScore >= 620)
            {
                rate=.058;
                cout << "Your interest rate is 5.8%\n";
            }
        else if (creditScore >= 580)
            {
                rate=.0655;
                cout << "Your interest rate is 6.55%\n";
            }
        else if (creditScore >= 500)
            {
                rate=.083;
                cout << "Your interest rate is 8.3%\n";
            }
    }
    totalPayments = years * 12;
    monthlyPayment = homePrice * [[rate * (1 + rate)pow(totalPayments)] / [(1 + rate)pow(totalPayments) - 1]];
    mortgageTotal = monthlyPayment * totalPayments;

    cout << "Your mortgage will cost approximately " << mortgageTotal << " and your monthly payment will be " << monthlyPayment << endl;
return 0;

}

但是，当我编译它时，出现以下错误：

Errors

我只是不了解错误以及它们为什么在那里。

如果有人可以帮助我，我将不胜感激。

谢谢。

Answer 1

虽然您的数学公式同时使用[]和()来对表达式进行分组，但在C ++中只能以这种方式使用()。

pow是一个函数调用，而不是您似乎正在使用的就地运算符。它必须看起来像pow(1 + rate, totalPayments)。

您的if也在做分配（=）而不是比较（==）。实际上，您的代码将仅跟随第一个if，因为它将years设置为15。

Answer 2

您的抵押贷款公式似乎有误。试试这个

monthlyPayment = homePrice * ((rate * pow(1 + rate, totalPayments)) /  
(pow(1.00 + rate, totalPayments) - 1));

C ++按揭付款计算器公式

2 个答案: