C++中的数组你真的理解了吗

1.数据类型 数组名[数组长度];
2.数据类型 数组名[数组长度]={值1,值2,值3,...};
3.数据类型 数组名[]={值1,值2,值3,...};

#include<iostream>
using namespace std;
int main()
{	
	//第一种定义数组
	int arr[5] ;
	memset(arr, 0, sizeof(arr));//初始化为0，否则为随机数
	arr[0] = 10;
	arr[1] = 10;
	arr[2] = 10;
	arr[3] = 10;
	arr[4] = 10;
	//访问数组
	for (int i = 0; i < 5; i++) 
	{
		cout << arr[i] << " ";
	}
	cout << endl;
	//第二种定义数组
	//如果在初始化的时候没有填充完，剩余的会用0来填充。
	int brr[5] = { 20,20,20,20 };
	for (int i = 0; i < 5; i++)
	{
		cout << brr[i] << " ";
	}
	cout << endl;
	//第三种定义数组
	char crr[] = { '3','3','3','3','c'};
	for (int i = 0; i < 5; i++)
	{
		cout << crr[i] << " ";
	}
	system("pause");
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
	//1.统计内存
	int arr[5] = { 1,2,3,4,5 };
	cout << "整个数组占用内存空间为：" << sizeof(arr) << endl;
	cout << "每个元素占用内存空间为：" << sizeof(arr[0]) << endl; //元素内存相同，所以只看一个就可以了。
	//2.查看数组首地址
	cout << "数组的首地址为(十六进制)：" << arr << endl;
	cout << "数组的首地址为(十进制)：" << (int)arr << endl;
	cout << "数组的第一个元素地址为(十进制)：" << (int)&arr[0] << endl;
	cout << "数组的第二个元素地址为(十进制)：" << (int)&arr[1] << endl;
	//会发现差4个字节，就是一个整型数组的内存大小。
	//3.数组名是常量，不可以想更改数组元素那样更改数组名
	//arr=crr
	system("pause");
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
	int arr[5] = { 300,350,200,400,250 };
	int size = sizeof(arr) / sizeof(arr[0]);
	int max = 0;
	for (int i = 0; i < size; i++)
	{
		if (arr[i] > max) { max = arr[i];}
	}
	cout << "最重的小猪体重为：" << max << endl;
	system("pause");
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
	int arr[5] = { 1,3,5,9,4 };
	int size = sizeof(arr) / sizeof(arr[0]);
	int start = 0;
	int end = size - 1;
	int temp = 0;
	//打印逆置前的数组
	cout << "数组逆置前：" << endl;
	for (int i = 0; i < size; i++)
	{
		cout << arr[i] << " ";
	}
	//逆置
	while (start < end)
	{
		temp = arr[start];
		arr[start] = arr[end];
		arr[end] = temp;
		start++;
		end--;
	}
	//打印逆置后的数组
	cout << "数组逆置后：" << endl;
	for (int i = 0; i < size; i++)
	{
		cout << arr[i] << " ";
	}
	system("pause");
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
	int arr[] = { 4,8,0,5,7,1,3,0};
	int size = sizeof(arr) / sizeof(arr[0]);
	//打印排序前的数组
	cout << "数组排序前：" << endl;
	for (int i = 0; i < size; i++)
	{
		cout << arr[i] << " ";
	}
	cout << endl;
	//冒泡排序
	for (int i = 0; i < size-1; i++)  //从0开始,共有size-1轮
	{
		for (int j = 0; j + i < size  - 1; j++) //每轮的比较次数与当前轮数相加小于size-1
		{
			if (arr[j] > arr[j + 1]) 
			{
				int temp = arr[j];
				arr[j] = arr[j+1];
				arr[j + 1] = temp;
			}
		}
	}
	cout << "数组排序后：" << endl;
	for (int i = 0; i < size; i++)
	{
		cout << arr[i] << " ";
	}
	cout << endl;

	system("pause");
	return 0;
}

1.数据类型 数组名[行数][列数];
2.数据类型 数组名[行数][列数]={{数据1,数据2},{数据3,数据4}};
3.数据类型 数组名[行数][列数]={数据1,数据2,数据3,数据4};
4.数据类型 数组名[][列数]={数据1,数据2,数据3,数据4};

#include<iostream>
using namespace std;
int main()
{	
	//1.数据类型 数组名[行数][列数];
	//2.数据类型 数组名[行数][列数] = { {数据1,数据2},{数据3,数据4} };
	//3.数据类型 数组名[行数][列数] = { 数据1,数据2,数据3,数据4 };
	//4.数据类型 数组名[][列数] = { 数据1,数据2,数据3,数据4 };
	//1.
	int arr[2][3];
	arr[0][0] = 0;
	arr[0][1] = 1;
	arr[0][2] = 2;
	arr[1][0] = 3;
	arr[1][1] = 4;
	arr[1][2] = 5;
	for (int i = 0; i < 2; i++) 
	{
		for (int j = 0; j < 3; j++) 
		{
			cout << arr[i][j] << "\t";
		}
		cout << endl;
	}
	cout << endl;
	//2.
	int brr[2][3] =
	{ 
		{1,2,3},
	    {4,5,6}
	};
	for (int i = 0; i < 2; i++)
	{
		for (int j = 0; j < 3; j++)
		{
			cout << brr[i][j] << "\t";
		}
		cout << endl;
	}
	cout << endl;
	//3.
	int crr[2][3] = { 1,2,3,4,5,6 };
	for (int i = 0; i < 2; i++)
	{
		for (int j = 0; j < 3; j++)
		{
			cout << crr[i][j] << "\t";
		}
		cout << endl;
	}
	cout << endl;
	//4.
	int drr[][3] = { 1,2,3,4,5,6 };
	for (int i = 0; i < 2; i++)
	{
		for (int j = 0; j < 3; j++)
		{
			cout << drr[i][j] << "\t";
		}
		cout << endl;
	}
	system("pause");
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
	int arr[2][3] =
	{
		{1,2,3},
		{4,5,6}
	};
	cout << "二维数组占用内存为：" << sizeof(arr) << endl;
	cout << "某一行占用内存为：" << sizeof(arr[0]) << endl;
	cout << "一个元素占用内存为：" << sizeof(arr[0][0]) << endl;
	int row = sizeof(arr) / sizeof(arr[0]);
	int column = sizeof(arr[0]) / sizeof(arr[0][0]);
	cout << "数组的行数为：" << row << "\n" << "数组的列数为：" << column << endl;
	cout << "二维数组的首地址是（16进制）：" << arr << endl;
	cout << "二维数组的首地址是（10进制）：" << (int)arr << endl;
	cout << "第一行首地址是（10进制）：" << (int)arr[0] << endl;
	cout << "第二行首地址是（10进制）：" << (int)arr[1] << endl;
	//会发现第一行和第二行差12，正好三个整型元素
	cout << "第二行第一个元素地址是（10进制）：" << (int)&arr[1][0] << endl;//直接使用arr[1][0]是查看这个元素内容，需要用&取地址。
	system("pause");
	return 0;
}

#include<iostream>
using namespace std;
//vs快捷键crtl+d可以直接把本行复制到下行
int main()
{
	int arr[3][3] =
	{
		{100,100,100},
		{90 ,50 ,100},
		{60, 70 ,80 }
	};
	cout << "成绩情况为：" << endl;
	for (int i = 0; i < 3; i++) 
	{
		for (int j = 0; j < 3; j++) 
		{
			cout << arr[i][j] << " ";
		}
		cout << endl;
	}
	string names[3] = { "张三","李四","王五" };
	for (int i = 0; i < 3; i++)
	{
		int sum = 0;
		for (int j = 0; j < 3; j++)
		{
			sum += arr[i][j];
		}
		cout << names[i] << "的总成绩为：" << sum << endl;
	}
	system("pause");
	return 0;
}