并行电路

Question

我在编程任务时遇到了问题。我需要计算并联和串联电路的总电阻值。我有串联电路的功能，但我的问题是，当我尝试计算并联电路的总电阻时，我的返回值为1。我怎么能解决任何建议，这

// project.cpp : Defines the entry point for the console application. 
    // 

    #include "stdafx.h" 
    #include <iostream> 
    #include <math.h> 

    using namespace std; 

    void menu() 
    { 
     cout <<"\t\t\tLab 2 Menu Driven Algorithms" << endl; 
     cout <<"\t\t Calculating Parallel and Series Resistance" << endl; 
     cout <<"1)\tSeries" << endl; 
     cout <<"2)\tParallel" << endl; 
     cout <<"3)\tQuit" << endl; 
    } 

    int series(int& num, int& sum) 
    { 
int answer; 
num = 0; 
sum = 0; 

do 
{ 
    cout << "Enter Resistor " << num+1 << " value, 0 to calculate: "; 
    cin >> answer; 
    cout << endl; 

    sum = sum + answer; 

    num++; 
} 
while(answer != 0);  

return sum; 
    } 

    double parallel (int& num, double& sum) 
    { 
double answer; 
num = 0; 
sum = 0.0; 
int counter = 0; 

do 
{ 
    cout << "Enter Resistor " << num+1 << " value, 0 to calculate: "; 
    cin >> answer; 
    cout << endl; 
    counter++; 

    sum = (1/answer) + sum; 
    cout << sum << endl; 

    num++; 
} 
while(answer != 0); 

return sum; 
    } 




    int main() 
    { 
char choice; 
int num = 0; 
int sum = 0; 
double sum2 = 0.0; 

menu(); 

cout <<"\n\nPlease enter a value from the menu: "; 
cin >> choice; 
cout << endl; 

while (choice != '3' && choice != 'q' && choice != 'Q') 
{ 


switch(choice) 
{ 
    case '1': cout << "Calculating Series Resistance" << endl; 
       cout << "The series resistance for the " << num-1 << " resistors is: " << series(num, sum) << " Ohms\n"; 
       system("pause"); 
       break; 
    case '2': cout << "Calculating Parallel Resistance" << endl; 
       cout << "The parallel resistance for the " << num-1 << " resistors is: " << parallel(num, sum2) << " Ohms\n"; 
       system("pause"); 
       break; 
    default: break; 

} 

system("cls"); 

menu(); 

cout <<"\n\nPlease enter a value from the menu: "; 
cin >> choice; 
cout << endl; 


} 
system("pause"); 

return 0; 
    } 

Answer 1

你可能想通过这种方式重写parallel()函数内部循环，让你永远不会处理的0值（在这种情况下会导致被零除） ：

cout << "Enter Resistor " << num+1 << " value, 0 to calculate: "; 
cin >> answer; 
cout << endl; 

while (answer != 0);  
{ 
    counter++; // NOTICE: This is never used for computation... 

    sum = (1/answer) + sum; 
    cout << sum << endl; 

    num++; 

    cout << "Enter Resistor " << num+1 << " value, 0 to calculate: "; 
    cin >> answer; 
    cout << endl; 
} 

的counter变量从未被用于计算的，所以我想你可以摆脱它。

另请注意，即使series()内部的循环也存在类似的问题，尽管您从不引起零除的事实并不会使其可见。