c++ - xCode 和 C++ 数组。这怎么可能？在 C++ 中声明一个没有大小的数组

Question

所以我创建了一个空数组并为其前 4 个元素分配了一些值。我正在将相同的代码复制到 Visual Studio 中，但该程序无法运行，因为它无法理解该行。那么在 C++ 中如何声明空数组？

#include <iostream>
using namespace std;

double inTotal(double quartersQuantity, double dimesQuantity, double 
nickelsQuantity, double penniesQuantity) {


double total = 0.25 * quartersQuantity + 0.10 * dimesQuantity + 0.05 * 
nickelsQuantity + 0.01 * penniesQuantity;

return total;

}

int main(int argc, const char * argv[]) {

string coinNames[] = {"quarters", "dimes", "nickels", "pennies"};
double coinQuantity[] = {};
int counter = 0;

for (string values : coinNames) {
    cout << "How many " << values << " do you have\n";
    cin >> coinQuantity[counter];
    counter++;

}

double total = inTotal(coinQuantity[0], coinQuantity[1], 
coinQuantity[2], coinQuantity[3]);
cout << "Your dollar value is " << total << " dollars." << endl;



return 0;
}

Answer 1

你可以用这种方式初始化数组。

int coinQuantity[4];  // declare the array
for (int i = 0; i < 4; i++) // ...initialize it
{
    coinQuantity[i] = 0;
}