Đếm số từ trong 1 chuỗi

/************************Count words of string******************/
#include "stdio.h"
#include "conio.h"
#include "string.h"

#define MAX_LENGTH 100

int CountWord(char *string);

void main()
{
char str[MAX_LENGTH];
char c;
printf("\nNhap chuoi khong qua 100 ki tu: ");
fflush(stdin);
gets(str);
printf("\nChuoi '%s' co %d(tu)", str, CountWord(str));
getch();
}

// Ham dem so tu trong chuoi
int CountWord(char *str)
{
int count = 0;
int length = strlen(str);
int i;
bool isSpace = false;
for (i = 0; i < length; i++)
{
if (i == 0 && str[i] != ' ' && str[i] != '\t')
{
count++;
}
if (str[i] == ' ' || str[i] == '\t')
{
isSpace = true;
}
else if (isSpace)
{
count++;
isSpace = false;
}
}
return count;
}