Problem 32 : Pandigital products
Problem Statement
We shall say that an n-digit number is pandigital if it makes use of all the digits 1 to n exactly once; for example, the 5-digit number, 15234, is 1 through 5 pandigital.
The product 7254 is unusual, as the identity, 39 × 186 = 7254, containing multiplicand, multiplier, and product is 1 through 9 pandigital.
Find the sum of all products whose multiplicand/multiplier/product identity can be written as a 1 through 9 pandigital.
Solution
from collections import Counter
def pandigital(x):
a=str(x)
j=Counter(a)
val=0
for i in '123456789':
if i in j:
if j[i]==1:
val=val+1
if val==9:
return True
return False
p = set()
for i in range(2, 60):
start = 1234 if i < 10 else 123
for j in range(start, 10000//i):
if pandigital(str(i) + str(j) + str(i*j)): p.add(i*j)
print(sum(p))
Output
45228