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Hello good people,

I am pretty much new in the programming sector. I recently started learning C, and C++. Reading a textbook is hard for me from my childhood. For the obvious reason, I decided to learn from the internet. I am solving basic problems from different websites. Today, I have got a problem that asks for a program where the input will be checked and let you know if it is a number or not! I have totally no idea about this. Could any of you please help me out to write such a program that checks if the input is a number?

I am looking forward to having your solutions. Many thanks.

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Well, the thing you are willing to do is called Input-Validation in programming. Input validation is an important trick to know and understand. An invalid and irrelevant input can crash the whole system. So, checking an input before the further process is a good practice. There are a couple of ways to validate input in  c++

I hope the below code snippet will help you to understand the whole process well.

#include <iostream>
using namespace std;

int main(){
    int num;
    cout << "Give me an Input: ";
    // Error Checkin algorithim
    while (!(cin >> num)){
        cout << "ERROR: a number must be entered: ";
        cin.ignore(132, '\n');      // Discarding previous input
    cout << "Your favorite number is: " << num << endl;
    cout << "Thanks. Bye." << endl;
    return 0;

Good Day!

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94,240 points

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