stl中copy()函数

C ++ STL std :: copy()函数 (C++ STL std::copy() function)

copy() function is a library function of algorithm header, it is used to copy the elements of a container, it copies the elements of a container from given range to another container from a given beginning position.

copy()函数是算法标头的库函数，用于复制容器的元素，它将容器的元素从给定范围复制到给定起始位置的另一个容器。

Note:To use copy() function – include <algorithm> header or you can simple use <bits/stdc++.h> header file.

注意：要使用copy()函数 –包括<algorithm>头文件，或者您可以简单地使用<bits / stdc ++。h>头文件。

Syntax of std::copy() function

std :: copy()函数的语法

    std::copy(iterator source_first, iterator source_end, iterator target_start);

Parameter(s):

参数：

• iterator source_first, iterator source_end – are the iterator positions of the source container.

  迭代器source_first，迭代器source_end –是源容器的迭代器位置。

• iterator target_start – is the beginning iterator of the target container.

  迭代器target_start –是目标容器的开始迭代器。

Return value: iterator – it is an iterator to the end of the target range where elements have been copied.

返回值： 迭代器 –它是目标元素已复制到目标范围末尾的迭代器。

Example:

例：

    Input:
//declaring & initializing an int array
int arr[] = { 10, 20, 30, 40, 50 };
//vector declaration
vector<int> v1(5);
//copying array elements to the vector
copy(arr, arr + 5, v1.begin());
Output:
//if we print the value
arr: 10 20 30 40 50
v1: 10 20 30 40 50

C ++ STL程序演示了std :: copy()函数的使用 (C++ STL program to demonstrate use of std::copy() function)

In this example, we are copying the array elements to the vector.

在此示例中，我们将数组元素复制到向量。

//C++ STL program to demonstrate use of
//std::copy() function
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int main()
{//declaring & initializing an int array
int arr[] = { 10, 20, 30, 40, 50 };
//vector declaration
vector<int> v1(5);
//copying array elements to the vector
copy(arr, arr + 5, v1.begin());
//printing array
cout << "arr: ";
for (int x : arr)
cout << x << " ";
cout << endl;
//printing vector
cout << "v1: ";
for (int x : v1)
cout << x << " ";
cout << endl;
return 0;
}

Output

输出量

arr: 10 20 30 40 50
v1: 10 20 30 40 50

Reference: C++ std::copy()

参考： C ++ std :: copy()

翻译自: https://www.includehelp.com/stl/std-copy-function-with-example.aspx

stl中copy()函数