Basic code using python

def fibonacci(n):

    # Write your code here.
    a=0
    b=1
    k.append(a)
    k.append(b)
    while(n+2>0):
        c=a+b
        a=b
        b=c
        k.append(c)
        n-=1

n = int(input())
k=[]
fibonacci(n)
print(k[n])

in swift. I made it through 2D array

func fibo(_ n: Int, _ memo: inout [Int: [Int]]) -> Int {
    if n < 2 { return n }
    if let values = memo[n] {
        return values[0] + values[1]
    }
    let value1 = fibo(n - 2, &memo)
    let value2 = fibo(n - 1, &memo)
    memo[n] = [value1, value2]
    return value1 + value2
}

func fibonacci (n: Int) -> Int { 
    var memo = [Int: [Int]]()
    return fibo(n, &memo)
}

// read the integer n
let n = Int(readLine()!)!

// print the nth fibonacci number
print(fibonacci(n: n))

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const fibonacci = (n, memo = []) => {
            if(n in  memo) return memo[n]; 
            if(n<=2) return 1;
            memo[n] = fibonacci(n-1, memo)+fibonacci(n-2, memo);
            return memo[n];
    }
    fibonacci(2); 

php

function fibonacci($n, $result = [0,1]) {
    if (isset($result[$n])) {
        return $result[$n];
    }
    
    $length = count($result);
    $result[] = $result[$length - 1] + $result[$length - 2];

    return fibonacci($n, $result);
}