c++ - 如何创建循环以遍历数组

Question

#include <stdio.h>
#include <iostream>
#include <conio.h>
#include <locale>
using namespace std;
class Equation
{
   private:
       double a, b, c, d;

    public:
    double fun[4];

    Equation()
    {}
    Equation(double a, double b, double c, double d)
    {
        fun[0] = a;
        fun[1] = b;
        fun[2] = c;
        fun[3] = d;
    }   
};



int main(int argc, char** argv) 
{

    for (int i = 0; i<5; i++)
    {
    Equation arr[i] = new Equation(1, 2, 3, 4);
    }
    return 0;
}

在这段代码中，我尝试创建(for 循环)和一个数组及其类型 Equation 并给它一些值

Equation arr[i] = new Equation(1, 2, 3, 4); 

但是当我运行代码时遇到错误(表达式必须具有常量值)。

Answer 1

你正在重新声明 arr[i]。

for (int i=0; i<5; i++){
    Equation arr[i] = new Equation(1, 2, 3, 4);
}

改用这个:

Equation arr[5]; // Array of Equation objects
for (int i=0; i<5; i++){
    arr[i] = Equation(1, 2, 3, 4); // assign different object
}