动态数组的分配与释放

一维数组

int m = 5;
int *arr = new int [m];
delete [] arr;

二维数组

#include <iostream>
using namespace std;

int main() 
{
    int m = 5, n = 10, v = 0;

    //创建指针数组
    int **arr = new int* [m];

    //为指针数组的每个元素创建一个一维数组，得到arr[m][n]
    for (int i = 0; i < m; i++)
    {
        arr[i] = new int[n];
    }

    for (int i = 0; i < m; i++)
    {
        for (int j = 0; j < n; j++)
        {
            arr[i][j] = v;
            v++;
        }
    }

    for (int i = 0; i < m; i++)
    {
        for (int j = 0; j < n; j++)
        {
            cout << arr[i][j] << " ";
        }
        cout << endl;
    }

    //使用后先删除一维数组
    for (int i = 0; i < m; i++)
    {
        delete [] arr[i];
    }

    //再删除指针数组
    delete arr;

    //也可以直接delete [] arr;

    return 0;
}

三维数组

int ***array3D;
int m = 5, n = 10, h = 20;

arr = new int **[m];
for( int i=0; i<m; i++ )
{
    arr[i] = new int *[n];
    for( int j=0; j<n; j++ )
    {
         arr[i][j] = new int [h];
    }
}
//释放
for( int i=0; i<m; i++ )
{
    for( int j=0; j<n; j++ )
    {
         delete arr[i][j];
    }
    delete arr[i];
}
delete arr;