while True:
n = int(input())
if n == 0:
break
L = [0]*(n+1)
s = input().split(",")
for i in s:
if "-" in i:
l,r = map(int,i.split("-"))
if l <= r:
for j in range(l,min(r+1,n+1)):
L[j] = 1
else:
if int(i) <= n:
L[int(i)] = 1
print(sum(L))