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

struct WordData {
    char word[101];
    char letter;
};

int count0ccurrence(struct WordData w) {
    int count = 0;
    for(int i = 0; i < strlen(w.word); i++) {
        count++;
    }
}
return count;
}
int main() {
    struct WordData data;
    scanf("%s",data.word);
    scanf(" %c",&data.letter);
    int result = count0ccurrence(data);
    if(result == 0)
    {
        printf("-1");
    }
    else
    {
        printf("%d", result);
    }
    return 0;
}