C :: IF Statements Within Loops

I've just started learning the C language, and I'm stuck on something that is probably quite simple.how to get IF statements working within WHILE loops. My code is below. I am trying to write a program to count the number of words in a sentence, and obviously stop counting after a full stop has been entered. I created a variable called 'spaces' which will increase by one after the user enters a space. However, when the IF statement is in place, the loop never terminates, even if I enter a full stop. When I delete the IF statement, the loop functions correctly.

Code:

#include <stdio.h>
int main()
{
char x;
char a;
char y;
int spaces = 0;
}

[code]....