C++ boost::trim用法及代码示例

此函数包含在“boost/algorithm/string” 库中。 Boost 字符串算法库提供了 STL 中缺少的 string-related 算法的通用实现。 trim 函数用于从字符串中删除所有前导或尾随空格。输入序列已就地修改。

trim_left():从字符串中删除所有前导空格。
trim_right():从字符串中删除所有尾随空格。
trim():从字符串中删除所有前导和尾随空格。

用法:

Template:
trim(Input, Loc);

参数：
Input:输入序列
Loc:用于‘space’ 分类的语言环境

返回：修改后的输入序列没有前导或尾随空格。

例子：

Input:” geeks_for_geeks ”
Output:Applied left trim:“geeks_for_geeks ”
Applied right trim:” geeks_for_geeks”
Applied trim:“geeks_for_geeks”
Explanation:
The trim_left() function removes all the leading white spaces.
The trim_right() function removes all the trailing white spaces.
The trim() function removes all the leading and trailing white spaces.

下面是使用函数boost::trim() 从字符串中删除空格的实现：

C++


// C++ program to remove white spaces
// from string using the function
// boost::trim function
#include <boost/algorithm/string.hpp>
#include <iostream>
using namespace boost::algorithm;
using namespace std;
  
// Driver Code
int main()
{
    // Given Input
    string s1 = "    geeks_for_geeks    ";
    string s2 = "    geeks_for_geeks    ";
    string s3 = "    geeks_for_geeks    ";
  
    // Apply Left Trim on string, s1
    cout << "The original string is:\""
         << s1 << "\" \n";
    trim_left(s1);
    cout << "Applied left trim:\""
         << s1 << "\" \n\n";
  
    // Apply Right Trim on string, s2
    cout << "The original string is:\""
         << s2 << "\" \n";
    trim_right(s2);
    cout << "Applied right trim:\""
         << s2 << "\" \n\n";
  
    // Apply Trim on string, s3
    cout << "The original string is:\""
         << s3 << "\" \n";
    trim(s3);
    cout << "Applied trim:\"" << s3
         << "\" \n";
  
    return 0;
}

输出：

The original string is:"    geeks_for_geeks    " 
Applied left trim:"geeks_for_geeks    " 

The original string is:"    geeks_for_geeks    " 
Applied right trim:"    geeks_for_geeks" 

The original string is:"    geeks_for_geeks    " 
Applied trim:"geeks_for_geeks"

时间复杂度：O(N)
辅助空间：O(1)

相关用法

注：本文由纯净天空筛选整理自newcybergypsy大神的英文原创作品 boost::trim in C++ library。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。