#!/usr/bin/env python

def fib( x ):
	x = x - 1
	a = 1
	b = 1
	
	for i in range( 1, x ):
		b = a + b
		a = b - a
	
	return b

def digitCount( x ):
	digits = 0;
	
	while x > 1:
		digits = digits + 1
		x = x / 10
	
	return digits + 1

testNumber = 1;

while digitCount( fib( testNumber ) ) != 1000:
	testNumber = testNumber + 1
	
print testNumber