How to Validate Integer User Input in C ?

How to Ensure User Input Matches Data Type in C

This code seeks to retrieve two integer values from the user and execute basic mathematical operations on them. However, it lacks the ability to verify if the user input is indeed integers.

To address this, we utilize the cin.fail() method. When an input operation fails (such as attempting to read a non-integer into an integer variable), cin.fail() returns true. This lets us implement error handling to guide the user in providing valid input.

int x;
cin >> x;

if (cin.fail()) {
    // Non-integer entered - handle input error
}

Furthermore, we can employ a loop to continuously request input until a valid integer is entered:

int x;

while (cin.fail()) {
    cout << "Please input an integer: ";
    cin >> x;
    cin.clear(); // Reset stream for subsequent operations
    cin.ignore(256, '\n'); // Clear input buffer
}

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