897 B | 897 chars
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta
# sys.setrecursionlimit(10**7)
BLANK = " "
# inp = input
inp = lambda : sys.stdin.readline().rstrip()
mii = lambda x = BLANK : [*map(int,inp().split(x))]
mfi = lambda x = BLANK : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print
def solve():
while 1:
n, l, r = mii()
if n == l == r == 0:
break
A = [ii() for _ in range(n)]
cnt = 0
for x in range(l, r + 1):
chk = True
for i in range(n):
if x % A[i] == 0:
if i % 2 == 0:
cnt += 1
break
else:
chk = False
break
else:
if chk and n % 2 == 0:
cnt += 1
p(cnt)
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()