Tim Varley Tim Varley

Euler 002 Java Solution

Even Fibonacci numbers
Feb 12, 2016
3 minute read

Problem

https://projecteuler.net/problem=2

Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:

\[1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...\]

By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.

Answer: 4613732

Solution

Solution002.java

package org.tvarley.euler.solutions;

import org.tvarley.euler.Solution;

public class Solution002 implements Solution {
  public String solve() {
    int sum = 0;
    int fib1 = 1;
    int fib2 = 1;
    int running = 0;

    while( running < 4000000 ) {
      if( (running % 2) == 0 ) {
        sum += running;
      }
      running = fib1 + fib2;
      fib2 = fib1;
      fib1 = running;
    }
    return Integer.toString(sum);
  }
}

See Also

# cpp go java php ruby rust javascript
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# cpp ruby
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