printing the char variable value using %d [duplicate]

Question

I was trying to get into c programming, but in a question a get stuck, please explain this.

 int main()
{
 char c = 255;
 c=c+10;
 printf("%d",c);
 return 0;
 }

the output it gave is

> 9

kindly explain this to me.

@Biffen my bad wrong research i suppose i will remove the comment — heeat
– heeat, Commented Feb 20, 2019 at 10:02

Darkpingouin · Accepted Answer · 2019-02-20 09:29:01Z

4

The maximum value of a char is 255.

By adding 10 to that number you get 265.

Because that value is not a suitable value for a char it will do 265 % 256 resulting 9

That's why your result is 9

answered Feb 20, 2019 at 9:26

Darkpingouin

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3 Comments

The modulo reasoning is not quite correct. You don't use module 255 but module 256.

Oh yeah because there are 256 values possible (0 to 255). You're right

If the char is signed then it is undefined behaviour.