# Rian J Stockbower

## Java solution to Project Euler Problem 25

The Fibonacci sequence is defined by the recurrence relation:

`Fn = F(n-1) + F(n-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 first term in the Fibonacci sequence to contain 1000 digits?

Running time: 36ms

Assessment: LOL.

```import java.math.BigInteger;   public class Problem025 { public static void main(String[] args) { long begin = System.currentTimeMillis();   BigInteger a = BigInteger.valueOf(1); BigInteger b = BigInteger.valueOf(2); BigInteger c = BigInteger.valueOf(0); BigInteger MAX = new BigInteger("1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000");   int i = 3; for (i = 3; b.compareTo(MAX) < 0; i++) { c = a.add(b); a = b; b = c; } System.out.println("i: " + i);   long end = System.currentTimeMillis(); System.out.println(end - begin + "ms"); } }```

Written by Rian

May 20th, 2011 at 7:00 am

Posted in Software

Tagged with , ,