UVa 494 - Kindergarten Counting Game

#include<stdio.h>
#include<string.h>
#include<ctype.h>
#define MAXN 5000

int main(){
char s[MAXN];
while(fgets(s,MAXN,stdin)){
int i,f=0,sum=0;
for(i=0;i<strlen(s);i++){
if(isalpha(s[i])&&f==0) f=1;
if(!isalpha(s[i])&&f==1){sum++;f=0;}
}
printf("%d\n",sum);
}
return 0;
}