## oschvr

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**← Problems**

# Even Fibonacci numbers

#### 27 days ago

###### 30/04/2019

**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.**

`1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22`

`package main import ( "fmt" "time" ) func main() { start := time.Now() i, c, sum := [...]int{1, 1}, 0, 0 for c < 4e6 { c = i[0] + i[1] i[0] = i[1] i[1] = c if c%2 == 0 { sum += c } } fmt.Println("Execution time: ", time.Since(start)) fmt.Print(sum, "\n") }`

Execution time: *276ns*

Answer

**4613732**