Solve problem 104 in Python

python/e104.py

@@ -0,0 +1,37 @@
+import math
+from itertools import permutations
+
+
+def first_n_digits(num, n):
+    # https://stackoverflow.com/questions/41271299/how-can-i-get-the-first-two-digits-of-a-number
+    p = int(math.log(num, 10)) - n + 1
+    if p < 0:
+        return num
+    return num // 10 ** (int(math.log(num, 10)) - n + 1)
+
+
+def is_end_pandigital(n, ps):
+    return (n % 10**9) in ps
+
+
+def is_start_pandigital(n, ps):
+    start = first_n_digits(n, 9)
+    return start in ps
+
+
+def euler_104():
+    a, b = 1, 1
+    ps = set([int("".join(map(str, p))) for p in permutations(range(1, 10))])
+    k = 3
+    while True:
+        a, b = b, a + b
+        if is_end_pandigital(b, ps) and is_start_pandigital(b, ps):
+            return k
+        k += 1
+
+
+if __name__ == "__main__":
+    solution = euler_104()
+    print("e104.py: " + str(solution))
+    assert(solution == 329468)
+