[C++知识库]【C++】动态数组类应用联系

目标:

使用动态数组类,动态分配空间并填入数字
使用对象生成并存放指定范围内的素数

代码:

#include <iostream>
using namespace std;
class Array
{
    int *s;
    int count;
    int length;

public:
    Array() : length(0), s(nullptr), count(0){};
    void gen(int limit)
    {
        for (int i = 2; i <= limit; i++)
        {
            int flag = 1;
            for (int j = 2; j < i; j++)
            {
                if (i % j == 0)
                {
                    flag = 0;
                    break;
                }
            }
            if (flag)
            {
                if (s == nullptr)
                {
                    s = new int[2];
                    length = 2;
                }
                if (count >= length)
                {
                    int *s_new = new int[length * 2];
                    memcpy(s_new, s, sizeof(int) * length);
                    length *= 2;
                    delete s;
                    s = s_new;
                }
                s[count++] = i;
            }
        }
    }
    void print(){
        for (int i = 0; i < count; i++)
        {
            cout<<s[i]<<" ";
        }
        
    }
};
int main(int argc, char const *argv[])
{
    Array a;
    a.gen(100);
    a.print();
}

评价

掌握好类中动态分配空间的创建,复制与回收过程即可