do while problem, please help

[berkxz]

Hi! I want to know what's my mistake in my code but in myself, i know, I haven't done anything wrong. So here's my question about the || operator, please see my code. I know i did correct but when I enter "x" or "X", it doesn't exit properly.

 #include <iostream>
#include <string>
using namespace std;




int main() {

char input;



do {

cout << "Welcome to learning lad" << endl;
cout << "This is where you can learn much more" << endl;
cout << "If you wish to exit, press x, if not, press any other key" << endl;
cin >> input;



}  while( input != 'x' || input != 'X');







return 0;
}

[JLBorges]

// while( input != 'x' || input != 'X');
while( input != 'x' && input != 'X'); // input is not 'x' and input is not 'X'
// ie. input is not one of { 'x', 'X' } 

[MiiNiPaa]

Your condition is flawed. Now it means
"repeat if input is not equal to 'x', or if input is not equal to 'X'"

Look what happens when you enter 'x':

input != 'x' → false
input != 'X' → true

false || true → true → repeat

You want && here.

[berkxz]

What i thought here is, if x is intered the bigger X will be flushed, if the bigger X was entered, the condition for the lowercase x will be flushed.