c++ check if cin didn't get int

To check if cin didn't get an integer in C++, you can use the fail function or the >> operator to check the state of the input stream. Here are the steps:

  1. Include the necessary header file: #include <iostream>

  2. Declare a variable to store the input: int num;

  3. Read the input using cin: std::cin >> num;

  4. Check the state of the input stream using the fail function or the >> operator:

  5. Using the fail function: cpp if (std::cin.fail()) { // Handle the case when cin did not get an integer }

  6. Using the >> operator: cpp if (!(std::cin >> num)) { // Handle the case when cin did not get an integer }

Both the fail function and the >> operator return true if the input was successful and false otherwise.

  1. Handle the case when cin did not get an integer. This could involve displaying an error message, clearing the input stream, or taking any other appropriate action.

Note: It is important to clear the input stream after a failed input to avoid getting stuck in an infinite loop. You can clear the input stream using the clear function and ignore any remaining characters using the ignore function:

std::cin.clear();
std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');

These steps will allow you to check if cin didn't get an integer in C++ and handle the situation accordingly.