642 B | 642 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:
d, m, y = mii()
if d == m == y == 0:
break
try:
k = datetime(y, m, d)
p("Valid")
except:
p("Invalid")
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()