我的输出结果在C++中是0。可能的问题是什么

Question

#include <iostream>
#include <stdio.h>
#include <string>

using namespace std;

void getInput(string name, float weekly_Pay){
    cout << "Please enter customer name" << endl;
    cin >> name;
    cout << "Enter weekly salary" << endl;
    cin >> weekly_Pay;
}

void calcFedTaxes(float weekly_Pay,float PIT_Rate, float SOSEC_Rate, float PIT, float SOSEC){
    PIT = weekly_Pay * PIT_Rate; 
    SOSEC = weekly_Pay * SOSEC_Rate;
}

void calcNetPay(float weekly_Pay, float PIT, float SOSEC, float weekly_Net_Pay){
    weekly_Net_Pay = weekly_Pay - (PIT + SOSEC);
}

void displayInfo(string name, float PIT, float SOSEC, float weekly_Net_Pay){
    cout << "Customer name is:" << name << endl;
    cout << "PIT is:" << PIT << endl;
    cout << "SOSEC is:" << SOSEC << endl;
    cout << "Weekly Pay is:" << weekly_Net_Pay << endl;
}

int main(){
    char response = 'n';
    string name =""; 
    float weekly_Pay = 0.0;
    float weekly_Net_Pay = 0.0;
    const float PIT_RATE = (0.2); 
    const float SOSEC_RATE = (0.08); 
    float SOSEC = (0.0);
    float PIT = (0.0);

    do {
        getInput(name, weekly_Pay);
        calcFedTaxes (weekly_Pay, PIT_RATE, SOSEC_RATE, PIT, SOSEC);
        calcNetPay (weekly_Pay, PIT, SOSEC, weekly_Net_Pay);
        displayInfo (name, PIT, SOSEC, weekly_Net_Pay);

        cout << "Enter n or N to end:";
        cin >> response;
        cout << endl;
    }
    while (!((response == 'n')  || (response == 'N')));
}

Answer 1

您的函数是按值获取输出参数的，因此它们对main()传递给它们的变量的副本起作用。函数对参数所做的任何更改都不会反映回main()。

要完成您正在尝试的操作，您需要通过引用传递输出参数：

#include <iostream>
#include <stdio.h>
#include <string>

using namespace std;

void getInput(string &name, float &weekly_Pay){
    cout << "Please enter customer name" << endl;
    cin >> name;
    cout << "Enter weekly salary" << endl;
    cin >> weekly_Pay;
}

void calcFedTaxes(float weekly_Pay, float PIT_Rate, float SOSEC_Rate, float &PIT, float &SOSEC){
    PIT = weekly_Pay * PIT_Rate; 
    SOSEC = weekly_Pay * SOSEC_Rate;
}

void calcNetPay(float weekly_Pay, float PIT, float SOSEC, float &weekly_Net_Pay){
    weekly_Net_Pay = weekly_Pay - (PIT + SOSEC);
}

void displayInfo(string name, float PIT, float SOSEC, float weekly_Net_Pay){
    cout << "Customer name is:" << name << endl;
    cout << "PIT is:" << PIT << endl;
    cout << "SOSEC is:" << SOSEC << endl;
    cout << "Weekly Pay is:" << weekly_Net_Pay << endl;
}

int main(){
    char response = 'n';
    string name =""; 
    float weekly_Pay = 0.0;
    float weekly_Net_Pay = 0.0;
    const float PIT_RATE = (0.2); 
    const float SOSEC_RATE = (0.08); 
    float SOSEC = (0.0);
    float PIT = (0.0);

    do {
        getInput(name, weekly_Pay);
        calcFedTaxes (weekly_Pay, PIT_RATE, SOSEC_RATE, PIT, SOSEC);
        calcNetPay (weekly_Pay, PIT, SOSEC, weekly_Net_Pay);
        displayInfo (name, PIT, SOSEC, weekly_Net_Pay);

        cout << "Enter n or N to end:";
        cin >> response;
        cout << endl;
    }
    while (!((response == 'n')  || (response == 'N')));
}

Live Demo