3.6 指针和多维数组

练习3.43

int main() 
	{
		
		int ia[3][4] = { {1,2,3,4},{5,6,7,8},{9,10,11,12} };
		//使用范围for语句管理迭代过程
		for (auto& i : ia) //对于外层数组的每一个元素
			for (auto j : i) //对于内层数组的每一个元素
				cout << j << endl;
	
		//使用下标运算符输出ia的元素
		for (size_t i = 0; i != 3;++i) //对于每一行
		{
			
			for (size_t j = 0; j != 4; ++j) //对于每一列
				cout << ia[i][j] << endl;
		}

		//使用指针输出ia的元素
		for (auto p = begin(ia);p != end(ia);++p)
			for (auto q = begin(*p); q != end(*p);++q)
				cout << *q << endl;
		
     }

练习3.44

int main() 
	{
		int ia[3][4] = { {1,2,3,4},{5,6,7,8},{9,10,11,12} };
		using int_array = int[4];
		typedef int int_array[4];

		//使用指针输出ia的元素
		for (int_array *p = ia;p != ia + 3;++p)
			for (int *q = *p; q != *p+4;++q)
				cout << *q << endl;
     }

练习3.45

//使用指针输出ia的元素
		for (auto p = begin(ia);p != end(ia);++p)
			for (auto q = begin(*p); q != end(*p);++q)
				cout << *q << endl;