C ++中的数组类
C++中的数组类足够高效,并且知道自己的大小。
用于对数组执行操作的函数是
size()=返回数组的大小,即返回数组元素的数量。
max_size()=返回数组中元素的最大数量。
get(),,at()operator[]=获取对数组元素的访问。
front()=返回数组的前元素。
back()=返回数组的最后一个元素。
empty()=如果数组大小为true,则返回true,否则返回false。
fill()=用特定值填充整个数组。
swap()=将一个数组的元素交换到另一个。
这是实现上述所有操作的示例-
范例程式码
#include<iostream>
#include<array>
using namespace std;
int main() {
array<int,4>a = {10, 20, 30, 40};
array<int,4>a1 = {50, 60, 70, 90};
cout << "The size of array is : ";
//size of the array using size() cout << a.size() << endl;
//数组中元素的最大数量
cout << "Maximum elements array can hold is : ";
cout << a.max_size() << endl;
// Printing array elements using at() cout << "The array elements are (using at()) : ";
for ( int i=0; i<4; i++)
cout << a.at(i) << " ";
cout << endl;
// Printing array elements using get() cout << "The array elements are (using get()) : ";
cout << get<0>(a) << " " << get<1>(a) << " "<<endl;
cout << "The array elements are (using operator[]) : ";
for ( int i=0; i<4; i++)
cout << a[i] << " ";
cout << endl;
//打印数组的第一个元素
cout << "First element of array is : ";
cout << a.front() << endl;
//打印数组的最后一个元素
cout << "Last element of array is : ";
cout << a.back() << endl;
cout << "The second array elements before swapping are : ";
for (int i=0; i<4; i++)
cout << a1[i] << " ";
cout << endl;
//交换a1值
a.swap(a1);
//交换后打印第一和第二数组
cout << "The first array elements after swapping are : ";
for (int i=0; i<4; i++)
cout << a[i] << " ";
cout << endl;
cout << "The second array elements after swapping are : ";
for (int i = 0; i<4; i++)
cout << a1[i] << " ";
cout << endl;
//检查是否为空
a1.empty()? cout << "Array is empty":
cout << "Array is not empty";
cout << endl;
//用1填充数组
a.fill(1);
//填充后显示数组
cout << "Array content after filling operation is : ";
for ( int i = 0; i<4; i++)
cout << a[i] << " ";
return 0;
}输出结果
The size of array is : 4 Maximum elements array can hold is : 4 The array elements are (using at()) : 10 20 30 40 The array elements are (using get()) : 10 20 The array elements are (using operator[]) : 10 20 30 40 First element of array is : 10 Last element of array is : 40 The second array elements before swapping are : 50 60 70 90 The first array elements after swapping are : 50 60 70 90 The second array elements after swapping are : 10 20 30 40 Array is not empty Array content after filling operation is : 1 1 1 1