如何动态创建一个二维已知的c++数组？

#include <iostream>

int main() {
    int rows = 3;
    int cols = 4;

    // 动态分配内存
    int** arr = new int*[rows];
    for (int i = 0; i < rows; ++i) {
        arr[i] = new int[cols];
    }

    // 初始化数组
    int count = 0;
    for (int i = 0; i < rows; ++i) {
        for (int j = 0; j < cols; ++j) {
            arr[i][j] = count++;
        }
    }

    // 打印数组
    for (int i = 0; i < rows; ++i) {
        for (int j = 0; j < cols; ++j) {
            std::cout << arr[i][j] << " ";
        }
        std::cout << std::endl;
    }

    // 释放内存
    for (int i = 0; i < rows; ++i) {
        delete[] arr[i];
    }
    delete[] arr;

    return 0;
}