用空格替换所有出现的字符串

给定一个字符串和一个子字符串，任务是用空格替换所有出现的子字符串。我们还需要删除因此而创建的尾随和前导空格。

例子：

Input: str = “LIELIEILIEAMLIECOOL”, sub = “LIE”
Output: I AM COOL
By replacing all occurrences of Sub in Str with empty spaces, we extract the secret message as I AM COOL.

Input: str = “XYZAXYZBXYZC”, sub = “XYZ”
Output: ABC
By replacing all occurrences of Sub in Str with empty spaces, we extract the secret message as ABC.

方法：

• 在给定的字符串Str 中，将所有出现的 Sub 替换为空格。
• 删除字符串开头和结尾不需要的空格。
• 打印修改后的字符串。

下面是上述方法的实现：

C++

// C++ implementation to extract 
// the secret message
#include 
using namespace std;
  
// Trim method implementation to remove 
// trailing and leading white-spaces
string trim(const string &s)
{
    auto start = s.begin();
    while (start != s.end() && 
           isspace(*start))
        start++;
  
    auto end = s.end();
    do
    {
        end--;
    } while (distance(start, end) > 0 && 
                    isspace(*end));
  
    return string(start, end + 1);
}
  
// Function to extract the secret message
string extractSecretMessage(string str, 
                            string sub)
{
    // Replacing all occurrences of
    // Sub in Str by empty spaces
    size_t pos;
    while ((pos = str.find(sub)) != string::npos)
        str.replace(pos, 3, " ");
  
    // Removing unwanted spaces in the
    // start and end of the string
    str = trim(str);
  
    return str;
}
  
// Driver code
int main(int argc, char const *argv[])
{
    string str = "LIELIEILIEAMLIECOOL";
    string sub = "LIE";
    cout << extractSecretMessage(str, sub) 
         << endl;
    return 0;
}
  
// This code is contributed by
// sanjeev2552

Java

// Java implementation to extract the secret message
import java.io.*;
import java.util.*;
  
class GFG {
  
    // Function to extract the secret message
    static String extractSecretMessage(String Str, String Sub)
    {
        // Replacing all occurrences of
        // Sub in Str by empty spaces
        Str = Str.replaceAll(Sub, " ");
  
        // Removing unwanted spaces in the
        // start and end of the string
        Str = Str.trim();
  
        return Str;
    }
  
    // Driver code
    public static void main(String args[])
    {
        String Str = "LIELIEILIEAMLIECOOL";
        String Sub = "LIE";
        System.out.println(extractSecretMessage(Str, Sub));
    }
}

Python3

# Python3 implementation to extract
# the secret message
  
# Function to extract the secret message
def extractSecretMessage(Str, Sub):
  
    # Replacing all occurrences of
    # Sub in Str by empty spaces
    Str= Str.replace(Sub, " ")
  
    # Removing unwanted spaces in the
    # start and end of the string
      
    return Str.strip()
  
# Driver code
Str = "LIELIEILIEAMLIECOOL"
Sub = "LIE"
print(extractSecretMessage(Str, Sub))
  
# This code is contributed 
# by ihritik

C#

// C# implementation to extract the 
// secret message 
using System;
  
class GFG 
{ 
  
// Function to extract the secret message 
static string extractSecretMessage(string Str, 
                                   string Sub) 
{ 
    // Replacing all occurrences of 
    // Sub in Str by empty spaces 
    Str = Str.Replace(Sub, " "); 
  
    // Removing unwanted spaces in the 
    // start and end of the string 
    Str = Str.Trim(); 
  
    return Str; 
} 
  
// Driver code 
public static void Main() 
{ 
    string Str = "LIELIEILIEAMLIECOOL"; 
    string Sub = "LIE"; 
    Console.WriteLine(extractSecretMessage(Str, Sub)); 
} 
} 
  
// This code is contributed by Ryuga

输出：

I AM COOL