Thread: Cant figure out what's wrong with my code..

I have an assignment:

Write a function which would determine whether a string is valid or not
by the following rules:
1.The string must include only the letters: 'x', 'y' and 'z'.
2.The string must end with 'z'.
3.Every time a 'y' is written it must come with another one attached 'yy'.
4.The number of 'x's must be odd.

e.g
Valid word: yyxyyxzxz
Invalid word: xyxyxz

Here is the code I wrote:

Code:

#include <stdio.h>
#include <string.h>


bool isValid (char s[])
{
	int count_x=0;


	if (s[(strlen(s)-1)]!='z') return false;


	for (int i=0; i<strlen(s);i++)
	{
		if (s[i]!='x' && s[i]!='y' && s[i]!='z') return false;
		if (s[i]=='x') count_x++;
		if ((s[i]=='y' && s[i+1]!='y') && (s[i]=='y' && s[i-1]!='y')) return false;
	}
	if (count_x%2==0) return false;
	else return true;


}


int main (void)
{
	char s1[10]="xxyyxzyz\0", s2[10]="helloxyz\0";


	if (isValid(s1)) printf ("s1 - valid\n");
	else printf ("s1 - invalid\n");


	if (isValid(s2)) printf ("s2 - valid\n");
	else printf ("s2 - invalid\n");
}

Please help me to figure out what is wrong
Thanks in advance.

I didnt understand, can you write the code you meant instead of my line 17?

A'right thanks to you all.!