Simple question on while loops

[danieldcc]

why does this work

printf ("Please enter a sentence");
while ((ch = getchar()) != '.') {   //i know that '\n' would terminate on new line character
if (ch == '.' || ch == '!' || ch == '?') 
break; 
sentence[i++] = ch;

but this doesnt?

printf ("Please enter a sentence");
while ((ch = getchar()) != '.' || ch != '!' || ch != '?') {
sentence[i++] = ch;

the scond code doesn't teminate

[tabstop]

Can you think of a value for ch where

ch != '.' || ch != '!' || ch != '?'

could possibly be false?

[danieldcc]

think that i'm getting this wrong but from what i understand this means.....

the value is true as long as ch does not equal '.' or '!' or '?'

[tabstop]

Right. And since ch can never equal all three of those at the same time, that means it is always true.

[danieldcc]

hahahhahahahahaahah, lol, i'm an idiot!!!

tks