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

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

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