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

struct Data(
    char word(101);
    char ch;
};

int main(){
    struct Data d;
    int count = 0;
    
    scanf("%s\n%c", d.word,&d.ch);
    
    for (int i = 0; d.word[i] != '\0'; i++) {
        if (d.word[i] == d.ch)
        count++;
    }
    
    if (count ==0){
        printf("-1\n");
    else {
        printf("%d\n", count);
    }
    
    return 0;
}