#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 WordData data;
     scanf("%s",data.word);
     scanf("%c",&data.letter);
     int result = countOccurence(data);
     if(result == 0)
      {
          printf("-1");
      }
     else
      {
          printf("%d",result);
      }
     return 0; 
 }