Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

uint8_t does not take two digit inputs

Tags:

c++

uint

This is my test code

#include<iostream>
using namespace std;
int main() 
{
    uint8_t a;
    while(1)
    {
        cin>>a;
        if(a == 0) break;
        cout<<"Input is "<<a<<endl;
    }
}  

When I execute (with my inputs), this is what I get

1
Input is 1
2
Input is 2
12
Input is 1
Input is 2
0
Input is 0
3  
Input is 3

Problem1: It takes input 12 as two separate inputs

Problem2: Condition if a==0 doesn't work

What might be the problems?

like image 201
Nick Avatar asked Jul 03 '12 10:07

Nick


2 Answers

uint8_t is a typedef for an unsigned char. This means that one character will be read from cin.

When "0" is read it is actually the ascii value of the character '0' commonly 48, which is not zero hence the equality check fails.

like image 58
hmjd Avatar answered Sep 18 '22 10:09

hmjd


uint8_t is the same as a char, so trying to extract one from cin probably just gives you the next character to be typed.

The values to receive are then not character-translated-to-int, but the ascii values of the inputs. When you type 0 you're getting ascii \0 rather than int zero, so your test for zero isn't triggered. Try if( a == '0') to see what I mean.

like image 29
RobH Avatar answered Sep 19 '22 10:09

RobH