# your code goes here
m = int(raw_input())
import os
from os.path import commonprefix
k1 = raw_input()
k2 = raw_input()
l1 = list(k1)
l2 = list(k2)
lf = []
ls = []
for i in range(m):
s = l2.pop(0)
l2.append(s)
ln = []
ln.append(l1)
ln.append(l2)
lf.append(len(os.path.commonprefix(ln)))
f = max(lf)
print lf.index(f)+1
IyB5b3VyIGNvZGUgZ29lcyBoZXJlCm0gPSBpbnQocmF3X2lucHV0KCkpCmltcG9ydCBvcwpmcm9tIG9zLnBhdGggaW1wb3J0IGNvbW1vbnByZWZpeAprMSA9IHJhd19pbnB1dCgpCmsyID0gcmF3X2lucHV0KCkKbDEgPSBsaXN0KGsxKQpsMiA9IGxpc3QoazIpCQoKbGYgPSBbXQpscyA9IFtdCmZvciBpIGluIHJhbmdlKG0pOgoJcyA9IGwyLnBvcCgwKQoJbDIuYXBwZW5kKHMpCglsbiAgPSBbXQoJbG4uYXBwZW5kKGwxKQoJbG4uYXBwZW5kKGwyKQoJbGYuYXBwZW5kKGxlbihvcy5wYXRoLmNvbW1vbnByZWZpeChsbikpKQoJCmYgPSBtYXgobGYpCnByaW50IGxmLmluZGV4KGYpKzEK