#include<stdio.h>
#include<ctype.h>
int countVowels(char*str){
    int count=0;
    while(*str){
        char ch=tolower(*str);
        if(ch == 'a'||ch == 'e'||ch == 'i'||ch == 'o'||ch == 'u'){
            count++;
        }
        str++;
    }
    return count ==0 ? -1 : count;
}
int main(){
    char str[100];
    printf("Enter a string:");
    fgets(str, sizeof(str),stdin);
    str[strcspn(str,"\n")]=0;
    printf("%d\n",countVowels(str));
    return 0;
}