#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Autor: Alexey V. Polurotov
# e-mail: niimailtah@gmail.com
# Common nick: Niimailtah
# ----------------------------------------------------------------------------
# https://projecteuler.net/problem=25
# 1000-digit Fibonacci number
# Problem 25
#
# The Fibonacci sequence is defined by the recurrence relation:
#    Fn = Fn−1 + Fn−2, where F1 = 1 and F2 = 1.
#
# Hence the first 12 terms will be:
#
#    F1 = 1
#    F2 = 1
#    F3 = 2
#    F4 = 3
#    F5 = 5
#    F6 = 8
#    F7 = 13
#    F8 = 21
#    F9 = 34
#    F10 = 55
#    F11 = 89
#    F12 = 144
#
# The 12th term, F12, is the first term to contain three digits.
#
# What is the index of the first term in the Fibonacci sequence to contain 1000 digits?
from libs.fibonacci import fibonacci
from time import clock

now = clock()
index = None
for f, index in fibonacci():
    if len(str(f)) == 1000:
        break

print(index)
print("time={0}".format(clock() - now))
