C++多维数组

一维数组

int ia[] = {0,1,2,3,4,5,6,7,8,9}; //ia是数组

多维数组

C++ 中并没有多维数组，它就是数组的数组。

int ia[3][4];

初始化

int ia[3][4] = {
    {0, 1, 2, 3},
    {4, 5, 6, 7},
    {8, 9, 10, 11}
};
//等价于
int ia[3][4] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
//显示初始化每行的首元素
int ia[3][4] = { {0} , {4} , {8}};
//显示初始化第一行
int ix[3][4] = {0, 3, 6, 9};

引用

下标引用

通过ia[i][j]方式引用下标：

constexpr size_t rowCnt = 3, colCnt = 4;
int ia[rowCnt][colCnt];

for (size_t i = 0; i != rowCnt; i++) {
  for (size_t j = 0; j != colCnt; j++) {
    ia[i][j] = i * colCnt + j;
  }
}

指针引用

Point root_points[2][4];
root_points[0][0] = Point(215,220);
root_points[0][1] = Point(460,225);
root_points[0][2] = Point(466,450);
root_points[0][3] = Point(235,465);

root_points[1][0] = Point(800,800);
root_points[1][1] = Point(800,800);
root_points[1][2] = Point(800,800);
root_points[1][3] = Point(800,800);

//Point* ppt[1] = {root_points[0]}; //此时ppt[1]是第一行数据的首地址，为215,220
  Point* ppt[1] = {root_points[1]}; //此时ppt[1]是第二行数据的首地址，为800,800

参考链接：
https://zhuanlan.zhihu.com/p/65862735