%% 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.

%% call the following function by using prob_002(4000000)

function y=prob_002(x)
  a = 1;
  b = 2;
  y = b;
  c=a+b;
  while c<=x % change this to hard-coded value to get the correct result
    a=b;
    b=c;
    c=a+b;
    if mod(c,2) == 0
      y = y+c
    end
  end
end
