KOTLIN Code

fun main(args: Array<String>) {
    val t = readLine()!!.trim().toInt()

    for (tItr in 1..t) {
        val n = readLine()!!.trim().toLong()
        createFibonacciSum(n)
    } 
}

private fun createFibonacciSum(n: Long){
    var left = 0L
    var middle = 1L
    var sum = 0L
    var i = 0
    while(i< n && (middle + left)< n){
        var right = middle + left
        left = middle
        middle = right
        if(right % 2L == 0L) sum += right
        i++ 
    }
    println(sum)
}

a very optimized solution with recursion

python def fib_sum_even(n, current, nextnum, sum_even): if current>n: return sum_even if current % 2 == 0: sum_even += current return fib_sum_even(n, nextnum, current+nextnum, sum_even)

include

include

using namespace std; int main(){ int n; cin >> n; for (int a = 0; a < n; a++){ long n; cin >> n;

    long sum = 0;
    long x1 =1,  x2=2;

    while (x2 <=n){
        if (x2 % 2 == 0){
            sum += x2;
        }
        long next = x1+x2;
        x1=x2;
        x2 = next;
    }
    cout << sum << endl;
}
return 0;

}

every even fibinoci number follows a pattern {2,8,34,144} if you look at 8 it is 2*4+0, 34 it is 8*4+2 , 144 it is 34*4+8

n = int(input().strip()) prev=0 i=2 s=0 tenp=0 while i<=n: s+=i temp=i i=i*4+prev prev=temp print(s)