#include<stdio.h>
#include<string.h>
struct WordData{
    char str[101];
    char letter;
};
int countOccurrence(struct WordData w){
    int count = 0;
    for(int i = 0;i<strlen(w.str);i++){
        if(w.word[i]==w.letter){
        count++;    
        }
        
    }
    return count;
}
int main(){
    struct WordData data;
    scanf("%s",data.word);
    scanf("%c",&data.;letter);
    int result = countOccurrence(data);
    if(result == 0)
    {
        printf("-1");
    }
    else{
        printf("%d",result);
    }
    return 0;
}