Go: package main

/*
フィボナッチ数列
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"log"
	"os"
	"strconv"
	"strings"
)

func fibWithMemo(n int, memo map[int]int) int {
	if n == 0 || n == 1 {
		return 1
	}
	if val, ok := memo[n]; ok {
		return val
	}
	memo[n] = fibWithMemo(n-1, memo) + fibWithMemo(n-2, memo)
	return memo[n]
}

func fib(n int) int {
	memo := make(map[int]int)
	return fibWithMemo(n, memo)
}

func main() {
	scanner := makeScanner(1024)
	n := eGetInt(scanner)
	fmt.Println(fib(n))
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

type ints []int

func (s ints) String() string {
	var buf bytes.Buffer
	buf.WriteString("[")
	sep := ""
	for _, v := range s {
		buf.WriteString(fmt.Sprintf("%s%d", sep, v))
		sep = ", "
	}
	buf.WriteString("]")
	return buf.String()
}

func reverse(a ints) ints {
	r := make(ints, len(a))
	for i := 0; i < len(a); i++ {
		r[i] = a[len(a)-1-i]
	}
	return r
}
func max(a ints) (int, bool) {
	if len(a) == 0 {
		return 0, false
	}
	m := a[0]
	for _, e := range a {
		if e > m {
			m = e
		}
	}
	return m, true
}
func min(a []int) int {
	m := a[0]
	for _, v := range a {
		if v < m {
			m = v
		}
	}
	return m
}

func sum(a ints) int {
	if len(a) == 0 {
		return 0
	}
	sum := 0
	for _, e := range a {
		sum += e
	}
	return sum
}
func find(n int, a ints) int {
	for i, v := range a {
		if n == v {
			return i
		}
	}
	return -1
}

Python: n = int(input())


F = [0] * (n + 1)

F[0] = 1
F[1] = 1

for i in range(2, len(F)):
    F[i] = F[i - 1] + F[i - 2]

print(F[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 = int(input())
if n != 0 and n != 1:
    fibo_list = []
    fibo_list.append(n - 1)
    fibo_list.append(n - 2)
    fib(n - 1, n - 2, fibo_list)
else:
    print(1)

Python: class Fib():
    f = [1] * 50
    def fib(self, n):
        for i in range(2, n + 1):
            self.f[i] = self.f[i - 1] + self.f[i - 2]
        return(self.f[n])

x = Fib()
print(x.fib(int(input())))

Python: # -*- coding: utf_8 -*-

n = int(input()) + 1
arr = [-1] * n

arr[0] = 1
arr[1] = 1

for i in range(2, len(arr)):
    arr[i] = arr[i - 1] + arr[i - 2]

print(arr[n - 1])

Python: import sys
sys.setrecursionlimit(10**7)

# n = int(input())
# a, b = map(int, input().split())
# int_list = list(map(int, input().split()))
# l = list(input().split())

mem = {}

def fib(n):
    if n == 0:
        return 1
    if n == 1:
        return 1
    if n not in mem.keys():
        res = fib(n-1) + fib(n-2)
        mem[n] = res
        return res
    else:
        return mem[n]

def solve():
    n = int(input())
    print(fib(n))

solve()

Python: n=int(input())
a=1
b=1
i=0
while i<n:
    a,b=b,a+b
    i+=1
print(a)

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: def fib_memo(n):
    memo = [0] * (n + 1)

    def _fib(n):
        if n <= 1:
            return 1
        if memo[n] != 0:
            return memo[n]
        memo[n] = _fib(n-1) + _fib(n-2)
        return memo[n]

    return _fib(n)

N = int(input())
print(fib_memo(N))

Python: def main():
    N = int(input())
    if N <= 1:
        print(1)
        return
    fib = [0]*(N+1)
    fib[0], fib[1] = 1, 1
    for i in range(2, N+1):
        fib[i] = fib[i-1] + fib[i-2]
    print(fib[N])


if __name__ == "__main__":
    main()

Python: n=int(input())
a=[]
a.append(1)
a.append(1)

mamo =[-1]*100

for i in range(2,n+1):
	a.append(a[i-1]+a[i-2])
	i+=1
	# if mamo[i]!=-1
	

print(a[n])

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

Python: def fib(n):
    F = {0:1, 1:1}
    def fibonacci(n):
        ans = F.get(n,-1)
        if ans > 0: return ans
        F[n] = fibonacci(n-1) + fibonacci(n-2)
        return F[n]
    return fibonacci(n)
        
if __name__=='__main__':
    print(fib(int(input())))

Python: n = int(input().strip())
if n <= 1:
    print(1)
    raise SystemExit
prev1 = 1
prev2 = 1
for i in range(2, n+1):
    fib = prev2 + prev1
    prev2, prev1 = prev1, fib
print(fib)

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: def fib2(n):
    a1, a2 = 1, 0
    while n > 0:
        a1, a2 = a1 + a2, a1
        n -= 1
    return a1


n = int(input())

print(fib2(n))

Python: 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)

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

Python: def fib(n):
    if n==0 or n==1:
        return 1
    else:
        if f[n]!=0:
            return f[n]
        else:
            f[n]=fib(n-1)+fib(n-2)
            return f[n]
f=[0]*45
n=int(input())

print(fib(n))

Python: n = int(input())

memo = [0 for _ in range(45)]

def fib_memo(n):
    if memo[n] != 0:
        return memo[n]
    elif (n == 0) or (n == 1):
        return 1
    else:
        memo[n] = fib_memo(n-1) + fib_memo(n-2)
        return memo[n]
    
print(fib_memo(n))

Python: # Algorithms and Data Structures 1
# Fibonacci Numbers
# Name: Ryuya Asada
# ID: s1260064


def fibonacci(n) -> int:
    a = 0
    b = 1
    c = 0
    for i in range(1, n+1):
        c = a + b
        a = b
        b = c
    
    return c


def main():
    n = int(input())
    print(fibonacci(n))
    pass


if __name__ == "__main__":
    main()

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

print(fibonacci(int(input())))

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

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

Python: import sys

input = sys.stdin.readline


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

    fib = [1] * 46
    for i in range(2, 46):
        fib[i] = fib[i - 1] + fib[i - 2]

    ans = fib[n]
    print(ans)


if __name__ == "__main__":
    main()