Remove whitespace in C++ string doesn't work [closed] - c++

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I have read these two questions already:
Remove spaces from std::string in C++
remove whitespace in std::string
For some reason, I can never get the solutions to work correctly. In my program, I collect input from the user and pass it to an std::string. From there, I want to remove all of the spaces in it. For example, if the user inputs "3 + 2", I would like it to change to "3+2".
What happens is, whatever is before the first string is kept. Here is my program:
#include <iostream>
std::string GetUserInput() {
std::cout << "Please enter what you would like to calculate: ";
std::string UserInput;
std::cin >> UserInput;
return UserInput;
}
int PerformCalculation(std::string Input) {
Input.erase(std::remove_if(Input.begin(), Input.end(), ::isspace), Input.end());
std::cout << Input;
return 0;
}
int main() {
std::string CalculationToBePerformed = GetUserInput();
int Solution = PerformCalculation(CalculationToBePerformed);
return 0;
}
So when I run this program and type in "3 + 2", the output is "3".
Here is my console:
Please enter what you would like to calculate: 3 + 2
3
Process finished with exit code 0
I cannot figure out how to resolve this. I even tried using a solution that involved using a regex to remove all the \s characters, and that gave me the same issue.

Answer 1

To read the complete line (up to terminating \n), you need to use e.g. std::getline(std::cin, UserInput);. Otherwise, you're currently reading text up to first whitespace character.