C ++错误：'int'之前的预期primary-expression？

Question

更新： 所以我能够编译并运行该程序，它似乎工作！然而，判断得分值2.3的变量 - 以奇怪的方式存储并且放弃计算。当我输入2.3时，商店价值是2.299999999998 - 这是为什么？ calcScore或最低和最高函数可能会出错，因为最终得分在输入分数时会减少0.3，2.3 - 5.5 - 5.5 - 5.5 - 8.5 - 任何想法？

// file name starSearch.cpp
// author: SK
// last modified: 03/19/2012

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

//function prototypes
void getJudgeData(double &);
void calcScore(double, double, double, double, double);
int findLowest(double, double, double, double, double);
int findHighest(double, double, double, double, double);

//declare variables
double score1;
double score2;
double score3;
double score4;
double score5;

int main()
{
    getJudgeData(score1); //Call getJudgeData for first judge score
    getJudgeData(score2); //Call getJudgeData for second judge score
    getJudgeData(score3); //Call getJudgeData for third judge score 
    getJudgeData(score4); //Call getJudgeData for fourth judge score
    getJudgeData(score5); //Call getJudgeData for fifth judge score
    calcScore(score1, score2, score3, score4, score5);    //calculate contestant score
    return 0; 
}

//
//Begin function prototypes definitions
//

//defines calcScore.
void calcScore(double score1, double score2, double score3, double score4, double score5)
{
    double total = (score1 + score2 + score3 + score4 + score5 - findLowest(score1, score2, score3, score4, score5) - findHighest(score1, score2, score3, score4, score5)) / 3;
    cout << setprecision(2);
    cout << "The contestant's final score is: " << total << endl;
}

//defines getJudgeData. this function asks each judge for their score.
void getJudgeData(double &score)
{
    cout << "Judge, enter the contestant's score: ";
    cin >> score;
    if (score < 0 || score > 10) //validate score between 0-10, else display error msg
    {
    cout << "ERROR: Enter a value in the range 0-10.\n";
    return getJudgeData(score);
    }
    return;
}

//defines findLowest. this function returns the lowest score entered.
int findLowest(double score1, double score2, double score3, double score4, double score5)
{
    if (score1 < score2 && score1 < score3 && score1 < score4 && score1 < score5)
    {
        return score1;
    }

    else if (score2 < score1 && score2 < score3 && score2 < score4 && score2 < score5)
    {   
        return score2;
    }

    else if (score3 < score1 && score3 < score2 && score3 < score4 && score3 < score5)
    {
        return score3;
    }

    else if (score4 < score1 && score4 < score2 && score4 < score3 && score4 < score5)
    {
        return score4;
    }

    else if (score5 < score1 && score5 < score2 && score5 < score3 && score5 < score4)
    {
        return score5;
    }
}

//defines findHighest. this functio returns the highest score entered.
int findHighest(double score1, double score2, double score3, double score4, double score5)
{
    if (score1 > score2 && score1 > score3 && score1 > score4 && score1 > score5)
    {
        return score1;
    }

    else if (score2 > score1 && score2 > score3 && score3 > score4 && score3 > score5)
    {   
        return score2;
    }

    else if (score3 > score1 && score3 > score2 && score3 > score4 && score3 > score5)
    {
        return score3;
    }

    else if (score4 > score1 && score4 > score2 && score4 > score3 && score4 > score5)
    {
        return score4;
    }

    else if (score5 > score1 && score5 > score2 && score5 > score3 && score5 > score4)
    {
        return score5;
    }
}

ORIGINAL：

我在第39行得到编译器错误，其中我的代数表达式用整数3写。我只是想弄清楚如何平均五个分数并删除最低和最高。确定哪个最高和最低的功能似乎是有序的..请帮助。

谢谢。

*// file name starSearch.cpp
// author: SK
// last modified: 03/19/2012

#include <iostream> 
using namespace std;

//function prototypes
void getJudgeData(double);
void calcScore();
int findLowest();
int findHighest();

//declare variables
double score1;
double score2;
double score3;
double score4;
double score5;

int main()
{
    getJudgeData(score1); //Call getJudgeData for first judge score
    getJudgeData(score2); //Call getJudgeData for second judge score
    getJudgeData(score3); //Call getJudgeData for third judge score 
    getJudgeData(score4); //Call getJudgeData for fourth judge score
    getJudgeData(score5); //Call getJudgeData for fifth judge score
    calcScore();    //calculate contestant score
    return 0; 
}

//
//Begin funtion prototypes definitions
//

//defines calcScore.
void calcScore(double score1, double score2, double score3, double score4, double score5)
{
    double total = score1 + score2 + score3 + score4 + score5 - int findLowest(a, b, c, d, e) - intfindHighest(a, b, c, d, e) / 3;
    cout << "The contestant's final score is: " << total << endl;
}

//defines getJudgeData. this function asks each judge for their score.
void getJudgeData(double score)
{
    cout << "Judge, enter the contestant's score: ";
    cin >> score;
    if (score < 0 || score > 10) //validate score between 0-10, else display error msg
    {
    cout << "ERROR: Enter a value in the range 0-10: ";
    cin >> score;
    }
    else
    return;
}

//defines findLowest. this function returns the lowest score entered.
int findLowest(double score1, double score2, double score3, double score4, double score5)
{
    if (score1 < score2, score3, score4, score5)
    {
        return score1;
    }

    else if (score2 < score1, score3, score4, score5)
    {   
        return score2;
    }

    else if (score3 < score1, score2, score4, score5)
    {
        return score3;
    }

    else if (score4 < score1, score2, score3, score5)
    {
        return score4;
    }

    else if (score5 < score1, score2, score3, score4)
    {
        return score5;
    }
}

//defines findHighest. this functio returns the highest score entered.
int findHighest(double score1, double score2, double score3, double score4, double score5)
{
    if (score1 > score2, score3, score4, score5)
    {
        return score1;
    }

    else if (score2 > score1, score3, score4, score5)
    {   
        return score2;
    }

    else if (score3 > score1, score2, score4, score5)
    {
        return score3;
    }

    else if (score4 > score1, score2, score3, score5)
    {
        return score4;
    }

    else if (score5 > score1, score2, score3, score4)
    {
        return score5;
    }
}*

Answer 1

这些功能分别称为findLowest和findHighest。 int是它们的返回类型，在调用它们时不应指定它们。

如果这引起你的困惑，我建议你找一本好的初学者级C ++书，并阅读函数声明和调用。

Answer 2

除了之前的答案，您的getJudgeData功能非常糟糕。它需要一个双引用，否则你永远不会修改原始变量，并且该函数毫无价值。此外，你无法防止法官输入错误分数两次。

void getJudgeData(double& score)
{
    cout << "Judge, enter the contestant's score: ";
    cin >> score;
    if (score < 0 || score > 10) //validate score between 0-10, else display error msg
    {
        cout << "ERROR: Enter a value in the range 0-10: ";
        return getJudgeData(score);
    }
    return;
}

这个简单的递归可以保护你免受每次输入错误数据的判断，并且它也会正确地修改原始变量，因为你的代码似乎写得很好。

Answer 3

问题在于您的界限：

double total = score1 + score2 + score3 + score4 + score5 - int findLowest(a, b, c, d, e) - intfindHighest(a, b, c, d, e) / 3;

您不应该在内嵌int标识符。编译器已经知道你的函数返回一个int。改为写

double total = score1 + score2 + score3 + score4 + score5 - findLowest(a, b, c, d, e) - findHighest(a, b, c, d, e) / 3;

正如其他人指出的那样，你可能想把它强制转换为双倍。在这种情况下，你会这样做。

double total = score1 + score2 + score3 + score4 + score5 - (double)findLowest(a, b, c, d, e) - (double)findHighest(a, b, c, d, e) / 3;

尽管如此，这实际上不会计算平均值，因此您应该使用括号来强制执行订单或操作。

double total = (score1 + score2 + score3 + score4 + score5 - (double)findLowest(a, b, c, d, e) - (double)findHighest(a, b, c, d, e)) / 3;

Answer 4

除了Chowlett提供的答案之外，您还需要重新考虑在findLowest和findHighest中使用逗号运算符。

例如，您在findHighest中的行

if (score1 > score2, score3, score4, score5)

基本上与

完全相同

if (score5)

这不是你想要的。

Answer 5

你想在那里演出吗？这是用括号（double）完成的，我认为double也是你想要施展的，虽然我不确定那里是否需要它。