a=int(input())
b=int(input())
count=0
for i in range(a,b+1):
for j in range(1,i+1):
if(i%j==0):
count+=1
if(count==2):
print(i)
YT1pbnQoaW5wdXQoKSkKYj1pbnQoaW5wdXQoKSkKY291bnQ9MApmb3IgaSBpbiByYW5nZShhLGIrMSk6CiAgICBmb3IgaiBpbiByYW5nZSgxLGkrMSk6CiAgICAgICAgaWYoaSVqPT0wKToKICAgICAgICAgICAgY291bnQrPTEKICAgIGlmKGNvdW50PT0yKToKICAgICAgICBwcmludChpKQogICAgICAgIA==