error: expected ')'
这是我在网上找到的一个 C++ 计算 compound interest 的代码，应该是比较旧版的，所以我 compile 时出现了以下错误error: expected ')'
while (choice! = -99)
^
note: to match this '('
while (choice! = -99)
请问谁能指导我怎么处理修改吗？
下面是完成的代码
#include <iostream>
#include <stdlib.h>
#include <cmath>
using namespace std;
double simple_interest (double principal, double rate, double time);
double compound_interest (double principal, double rate, double time);
double compound_interest_ear (double principal, double rate, double time, double period);
int main ()
{
double amount, principal, rate, time, interest, R;
int choice;
double SI, CI, EAR, Amount, period;
amount = principal = rate = time = interest = 0.0;
while (choice! = -99)
{
cout << "\n\n\n\n\n";
cout << "\t\t\tEnter Principal amount:"; cin >> principal;
cout << "\t\t\tEnter Rate (In percentage):"; cin >> R;
rate = R/100;
cout << "\t\t\tEnter Time (In Years):"; cin >> time;
cout << "\t\t\t" << principal << endl;
cout << "\t\t\t" << rate << endl;
cout << "\t\t\t" << time << endl;
cout << "\t\t\t************ MENU ********************" << endl;
cout << "\t\t\t1: Simple Interest" << endl;
cout << "\t\t\t2: Compound Interest" << endl;
cout << "\t\t\t3: Effective Annual Rate (Compound Interest)" << endl;
cout << "\t\t\t****************************************" << endl;
cout << "\t\t\tEnter You Choice:"; cin >> choice;
if(choice == 3)
{
cout << "\t\t\tNo of Period in a Year:";
cin >> period;
}
switch(choice)
{
case 1:
SI = simple_interest (principal, rate, time);
Amount = principal + SI;
cout << "\n\n\n";
cout << "\t\t\tSimple Interest =" << " "<< SI << endl;
cout << "\t\t\tTotal Amount =" << " " << Amount<< endl;
break;
case 2:
Amount = compound_interest(principal, rate, time);
CI = Amount - principal;
cout << "\n\n\n";
cout << "\t\t\tCompound Interest with Principal =" << " "
<<
Amount << endl;
cout << "\t\t\tTotal Compound Interest ="<< " " <<
CI << endl;
break;
case 3:
Amount = compound_interest_ear(principal, rate, time, period);
CI = Amount - principal;
EAR = pow((1 + (rate/period)),period)-1;
cout << "\n\n\n";
cout << "\t\t\tCompound Interest with Principal =" << " " <<
Amount << endl;
cout << "\t\t\tTotal Compound Interest =" << " " <<
CI << endl;
cout << "\t\t\tEffective Annual Rate =" << " " <<
EAR << endl;
cout << "\t\t\tNomianal Rate =" << " " <<
rate << endl;
break;
default:
cout << "\t\t\tSorry ! Try again";
break;
}
cout << "\n\n\n";
cout << "\t\t\tDo you want to Continue?" << endl;
cout << "\t\t\tEnter -99 to end" << endl;
cout << "\t\t\tOr Enter any other number to Continue:";
cin << choice;
}
system("PAUSE");
return EXIT_SUCCESS;
}
// Simple interest
double simple_interest(double principal, double rate, double time)
{
double SI = principal * rate * time;
double Amount = principal + SI;
return SI;
}
// Compound Interest
double compound_interest(double principal, double rate, double time)
{
double CI;
double Amount;
Amount = principal * pow((1 + rate),time);
return Amount;
}
// Compound Interest with the effective annual rate
double compound_interest_ear(double principal,double rate, double time,double period)
{
double CI, EAR, Amount;
period = period * time;
Amount = principal * pow((1 + (rate/period)),period);
return Amount;
}
