Go: package main

import "fmt"

func main() {
	var n int
	fmt.Scan(&n)

	x, y := int64(1), int64(1)

	for i := 0; i < n; i++ {
		x, y = y, x+y
	}

	fmt.Println(x)
}

Python: F = {}

def fib(n):
  global F
  if n < 0:
    print("error")
    exit()
  if n < 2:
    F[n] = 1
    return F[n]
#  F[n] = fib(n-1) + fib(n-2)
  F[n] = F(n-1) + F(n-2)
  return F[n]

n = int(input())
print(fib(n))
#n = int(input())
#print(fib(n))
#fib(44)
#for i in range(5+1):
#  print(F[i])

Python: # Fibonacci Number

N = int(input())
dp = [-1] * (N+1)
dp[0] = 1
dp[1] = 1
for i in range(2, N+1):
    dp[i] = dp[i-2] + dp[i-1]
print(dp[-1])

Python: def fib(n):
    if n == 0 or n == 1:
        return 1
    else :
        return fib(n - 1) + fib(n - 2)


print( fib( int( input() ) ) )

Python: n = int(input())
fib = [0] * (n+1)
fib[0] = 1
fib[1] = 1
for i in range(2, n+1):
  fib[i] = fib[i-1] + fib[i-2]
print(fib[n])

Python: n=int(input())
dp=[0]*(n+1)
dp[0],dp[1]=1,1
for i in range(2,n+1):
    dp[i]=dp[i-1]+dp[i-2]
print(dp[n])

Python: n = int(input())
fib_ls = [0] * (n+1)
fib_ls[0], fib_ls[1] = 1,1
for i in range(2,n+1):
    fib_ls[i] = fib_ls[i-1] + fib_ls[i-2]
print(fib_ls[n])

Python: A = {}
def fibonacci(n):
    global A
    if n == 0 or n == 1:
        A[n] = 1
        return A[n]
    if n in A:
        return A[n]
    else:
        A[n] = fibonacci(n - 2) + fibonacci(n - 1)
        return A[n]

n = int(input())
print(fibonacci(n))

Python: def fib(n):
    if n == 0 or n == 1:
        return 1
    return fib(n-1) + fib(n-2)

n = int(input())
print(fib(n))

Python: N = int(input())

DP = [0 for _ in range(N + 1)]
DP[0] = 1
DP[1] = 1

for i in range(2, N + 1):
    DP[i] = DP[i - 1] + DP[i - 2]

print(DP[N])

Python: n = int(input())

from functools import lru_cache
@lru_cache(maxsize=None)
def fibo(n: int):
    if n == 0 or n == 1:
        return 1
    return fibo(n-1) + fibo(n-2)

print(fibo(n))

Python: def fib(a, b, fiboli):
    if len(fiboli) < n:
        fiboli.append(fiboli[-1] + fiboli[-2])
        fib(fiboli[-1], fiboli[-1] + fiboli[-2], fiboli)
    else:
        print(fiboli[-1])
        print(fiboli)

# n = 4
n = int(input())
if n == 0 or n == 1:
    print(1)
elif n == 2:
    print(2)
else:
    fibo_list = []
    fibo_list.append(n - 1)
    fibo_list.append(n - 2)
    fib(n - 1, n - 2, fibo_list)

Python: f=[None for i in range(45)]

def fib(n):
    if n==0 or n==1:
        if f[n] is None:
            f[n] = 1
        return 1
    else:
        if f[n-2] is not None:
            f_n_2 = f[n-2]
        else:
            f_n_2 = fib(n-2)
            f[n-2] = f_n_2
        if f[n-1] is not None:
            f_n_1 =  f[n-1]
        else:
            f_n_1 = fib(n-1)
            f[n-1] = f_n_1
        f[n] = f_n_1 + f_n_2
        return f[n]
n = int(input())
print(fib(n))

Python: def main():
    n = int(input())
    fib = [1] * (n + 1)
    for i in range(2, n + 1):
        fib[i] = fib[i - 1] + fib[i - 2]
    print(fib[n])


if __name__ == "__main__":
    main()

Python: MAX_N = 44
_memo = [None for _ in range(MAX_N + 1)]
_memo [0] = _memo[1] = 1

def fibonacci(n):
    
    if _memo[n] is not None:
        return _memo[n]
    else:
        _memo[n] = fibonacci(n - 1) + fibonacci(n - 2)
        return _memo[n]

if __name__ == '__main__':
    n = int(input())
    print(fibonacci(n))

Python: def fibn(n):
    fib = [1,1]
    for i in range(2,n+1):
        fib.append(fib[i-2] + fib[i-1])
    return fib[n]
    
n = int(input())
print(fibn(n))

Python: from functools import lru_cache
n = int(input())

@lru_cache(maxsize=None)


def fib(n):
    if n==0 or n==1:
        return 1
   
    else:
        return fib(n-1)+fib(n-2)
        
print(fib(n))

Python: from functools import lru_cache


@lru_cache(maxsize=None)
def fib(n):
    """ http://docs.python.jp/3/library/functools.html """
    if n < 2:
        return n
    return fib(n-1) + fib(n-2)


class Fibonacci(object):
    memo = [1, 1]

    def get_nth(self, n):
        if n < len(Fibonacci.memo):
            return Fibonacci.memo[n]
        # print('fib({0}) not found'.format(n))
        for i in range(len(Fibonacci.memo), n+1):
            result = Fibonacci.memo[i-1] + Fibonacci.memo[i-2]
            Fibonacci.memo.append(result)
            # print('fib({0})={1} append'.format(i, result))
        return Fibonacci.memo[n]


if __name__ == '__main__':
    # ??????????????\???
    num = int(input())

    # ?????£??????????????°????¨????
    f = Fibonacci()
    result = f.get_nth(num)
    #result = fib(num+1)

    # ???????????????
    print('{0}'.format(result))

Python: n=int(input())
fib = [1,1]

for i in range(2,n+1):
    fib.append(fib[i-1]+fib[i-2])
    
print(fib.pop())

Python: def fib(n):
    n=int(n)
    F=[1,1]
    if n>=2:
        for i in range(1,n):
            F.append(F[i-1]+F[i])
    
    return F[n]
    
a=input(int())
fib(a)

Python: a=b=1
for i in range(int(input())):
    a,b=b,a+b
print(a)

Python: #!/usr/bin/env python3
# -*- coding: utf-8 -*-

import sys
import re
import math
import itertools
import functools
import logging

logging.basicConfig(level=logging.DEBUG, format="DBG: %(message)s")

def dbg(msg, *args, **kwargs):
    logging.debug(msg, *args, **kwargs)

def fib(n):
    assert n >= 0

    f0 = 1
    f1 = 1

    if n == 0: return f0
    if n == 1: return f1

    for _ in range(n-1):
        f2 = f1 + f0
        f0 = f1
        f1 = f2

    return f2

def main():
    n = int(input())

    print(fib(n))

if __name__ == "__main__": main()

Python: #!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys


def fib_1(n):
    if not n or n == 1:
        return 1
    return fib_1(n - 2) + fib_1(n - 1)


if __name__ == '__main__':
    _input = sys.stdin.readlines()
    index = int(_input[0])
    print(fib_1(index))

Python: def fibonacci_dp(n,lf):
    if n == 0 or n == 1:
        return lf[n]
    if n < len(lf):
        return lf[n]
    lf.insert(n,fibonacci_dp(n-2,lf) + fibonacci_dp(n-1,lf))
    return lf[n]

if __name__ == "__main__":
    n = int(input())
    lf = [1,1,]
    print(fibonacci_dp(n,lf))

Python: def make_fibonacchi(n: int):
    
    res = {}
    
    res[0] = 1
    res[1] = 1
    
    if n == 0 or n == 1:
        return 1
    
    for i in range(2, n + 1):
        res[i] = res[i-1] + res[i-2]
    
    return res[n]


n = int(input())
print(make_fibonacchi(n))

Python: n = int(input())

A = []
A.append(1)
A.append(1)

if n>1:
    for i in range(n-1):
        A.append(A[i]+A[i+1])

print(A[n])

Python: x = [1,1]
n = int(input())
for i in range(n):
    a=[x[i]+x[i+1]]
    x = x+a
print(x[n])

Python: a=1
b=1
c=[]
n=int(input())
c.append(a)
c.append(b)
for i in range(n):
  c.append(a+b)
  d=b
  b+=a
  a=d
print(c[n])

Python: n = int(input())

first = 1
second = 1
for i in range(n):
    second, first = first + second, second
print(val)

Python: n = int(input())
n1 = 1
n2 = 1
result = 0
if n < 2:
    result = 1
else:
    for i in range(n-1):
        result = n1 + n2
        n2 = n1
        n1 = result
print(result)

Python: n=int(input())
a=1
b=1
list=[]
list.append(a)
list.append(b)
for i in range(n):
  list.append(a+b)
  d=b
  b+=a
  a=d
print(list[n])

Python: N = int(input())
A = [0]*(N+1)
if N == 0 or N == 1:
    print(1)
else:
    A[0] = 1
    A[1] = 1
    for i in range(2, N+1):
        A[i] = A[i-1] + A[i-2]
    print(A[N])

Python: 


def make_fib(n):
    if n == 0 or n == 1: return 1
    if F[n] != -1: return F[n]
    else:
        F[n] = make_fib(n-1)+make_fib(n-2)
        return(F[n])

def fibonacci(n):
    if n == 0 or n == 1: return 1
    else: return(fibonacci(n-1)+fibonacci(n-2))

n = int(input())
F = [-1 for i in range(50)]
F[0] = F[1] = 1   #n=0 t0 1 pre-registered
print(make_fib(n))