import sys
s=input()
t=input()
if len(t)<2:
    if s.find(t)<0:
        print(0)
        sys.exit()
    print(-1)
else:
    n=len(t)
    k=0
    for i in range(len(s)):
        k=s.find(t,k)
        if k<0:
            print(i)
            sys.exit()
        k+=n-1
    print(k)