Python 104

src/104/README.md

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+https://projecteuler.net/problem=104
+
+
+
+The Fibonacci sequence is defined by the recurrence relation:
+Fn = Fn−1 + Fn−2, where F1 = 1 and F2 = 1.
+It turns out that F541, which contains 113 digits, is the first Fibonacci number for which the last nine digits are 1-9 pandigital (contain all the digits 1 to 9, but not necessarily in order). And F2749, which contains 575 digits, is the first Fibonacci number for which the first nine digits are 1-9 pandigital.
+Given that Fk is the first Fibonacci number for which the first nine digits AND the last nine digits are 1-9 pandigital, find k.
+
+

src/104/p104.py

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+import math
+
+pand2 = lambda x: '0' not in x and len(set(x)) == 9
+pand1 = lambda x: x % 3 == 0 and pand2(str(x))
+fndigits = lambda num, n: num // 10 ** (int(math.log(num, 10)) - n + 1)
+
+a, b = 1, 1
+for i in range(3, 1000000):
+    F = a + b
+    a, b = b, F
+    if pand1(a % 1000000000) and pand1(fndigits(a, 9)):
+        print(i - 1)
+        break
+