错误Nullptr未声明

Question

所以当我在学校编译它时,nullptr错误不会出现,我认为我可以通过添加一行来修复它,当我编译它,是否有另一种方法来摆脱它,另外两个错误,我不明白为什么我得到他们都没有.有人能解释至少nullptr错误吗？

main.cpp:在函数'int main()'中:

错误:此范围内未声明'array'

错误:此范围内未声明"小时"

错误:未在此范围内声明'nullptr'

    int main()
{
    float *studentData;
    int numStudents;
    int size;
    int average = getAverage(*array, *hours);
    int median = getMedian(hours);
    int mode = getMode(hours);

    cout << "How many students were surveyed?  ";
    cin >> numStudents;
    studentData = makeArray(numStudents);

     if (studentData == nullptr)
         cout << "Error allocating memory.";
     else
     {
         getFBData(studentData, numStudents);
         selectionSort(studentData, numStudents);

         for (int i = 0; i < numStudents; i++)
             cout << *(studentData + i) << endl;

         delete[] studentData;
     }

     getAverage(*array, hours);
     printArray(size, hours);
     getMedian(*array, hours);
     getMode(*array, hours);

    cout << "STATISTICS " << endl;
    cout << "\n  Mean: " << average;
    cout << "\n  Median: " << median;
    cout << "\n  Mode: " << mode;


    return 0;
}

Answer 1

在这一行:

int average = getAverage(*array, *hours);

你指的array和hours,但是你还没有宣布这些事情呢.代码的"学校版"必须是不同的.

回覆.的nullptr错误:那是在2011年加入到C++也许学校有上最新的编译器,但你在家里有一个较旧的编译器.如果您更改nullptr到0会被罚款.