Removing spaces from a string using Stringstream

Solution to removing spaces from a string is already posted here. In this article another solution using stringstream is discussed.

Algorithm:

1. Enter the whole string into stringstream.
2. Empty the string.
3. Extract word by word and concatenate to the string.

Program 1: Using EOF. 

CPP

// C++ program to remove spaces using stringstream
#include <bits/stdc++.h>
using namespace std;

// Function to remove spaces
string removeSpaces(string str)
{
    stringstream ss;
    string temp;

    // Storing the whole string
    // into string stream
    ss << str;

    // Making the string empty
    str = "";

    // Running loop till end of stream
    while (!ss.eof()) {

        // Extracting word by word from stream
        ss >> temp;

        // Concatenating in the string to be
        // returned
        str = str + temp;
    }
    return str;
}

// Driver function
int main()
{
    // Sample Inputs
    string s = "This is a test";
    cout << removeSpaces(s) << endl;

    s = "geeks for geeks";
    cout << removeSpaces(s) << endl;

    s = "geeks quiz is awesome!";
    cout << removeSpaces(s) << endl;

    s = "I love     to     code";
    cout << removeSpaces(s) << endl;

    return 0;
}

Output

Thisisatest
geeksforgeeks
geeksquizisawesome!
Ilovetocode

Time complexity: O(n) where n is length of string
Auxiliary space: O(n)

Program 2: Using getline(). 

CPP

// C++ program to remove spaces using stringstream
// and getline()
#include <bits/stdc++.h>
using namespace std;

// Function to remove spaces
string removeSpaces(string str)
{
    // Storing the whole string
    // into string stream
    stringstream ss(str);
    string temp;

    // Making the string empty
    str = "";

    // Running loop till end of stream
    // and getting every word
    while (getline(ss, temp, ' ')) {
        // Concatenating in the string
        // to be returned
        str = str + temp;
    }
    return str;
}
// Driver function
int main()
{
    // Sample Inputs
    string s = "This is a test";
    cout << removeSpaces(s) << endl;

    s = "geeks for geeks";
    cout << removeSpaces(s) << endl;

    s = "geeks quiz is awesome!";
    cout << removeSpaces(s) << endl;

    s = "I   love     to     code";
    cout << removeSpaces(s) << endl;

    return 0;
}

// Code contributed by saychakr13

Output

Thisisatest
geeksforgeeks
geeksquizisawesome!
Ilovetocode

Time complexity: O(n) 
Auxiliary Space: O(n)

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