Is this a bug in c/c++.. chars and strings inputs are considered as they were 0 in comparison!?

Question

Here is the code:
*****************

#include <iostream>
using namespace std;
int main() {
int x;
cout <<"Entrer your number: ";
cin >> x;
if(x > 0) {
cout <<"Positive" ;
} else if(x == 0) {
cout <<"Null" ;
} else if (x < 0){
cout <<"Negative" ;
} else {
cout <<"Invalid" ;
}
}
/* Try to give x the value of : ghgfh it will prints Null to the screen!! the same thing as 0 or just a letter f. what is the problem?? I wrote the same pgm in c and the same issue */
//I've tried it in JS and it worked as expected!!

Answer 1

Finally I got the right answers here:
https://io.hsoub.com/go/70469