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: # import bisect
# from collections import Counter, deque
# import copy
# from fractions import gcd

def resolve():
    N=int(input())

    # dp[i]はh[i]までにかかるコストの最小値
    dp = [float('inf') for _ in range(N+1)]
    dp[0] = 1
    dp[1]=1


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



resolve()

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


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

print(fib[-1])

Python: fib = [0]*45
fib[0] = 1
fib[1] = 1
for i in range(2, 45):
    fib[i] = fib[i-1] + fib[i-2]
x = int(input())
print(fib[x])

Python: def fib(n):
    f0, f1 = 1, 1

    for i in range(n - 1):
        f1, f0 = f1 + f0, f1

    return f1

n = int(input())
ans = fib(n)

print(ans)

Python: answer_list = [1, 1] + [None] * 43

def fib(num):
    ans = answer_list[num]
    if ans:
        return ans
    ans = fib(num - 1) + fib(num - 2)
    answer_list[num] = ans
    return ans

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

import sys


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


def fib_dp(n):
    fib_list[:1] = [1, 1]
    for i in range(2, n + 1):
        fib_list[i] = fib_list[i - 2] + fib_list[i - 1]
    return fib_list[n]


if __name__ == '__main__':
    _input = sys.stdin.readlines()
    index = int(_input[0])
    fib_list = [None] * index
    print(fib_dp(index))

Python: n=int(input())
DP=[0]*45
DP[0],DP[1]=1,1
for i in range(2,45):
    DP[i]=DP[i-1]+DP[i-2]
print(DP[n])

Python: #!/usr/bin/env python3

n = int(input())

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

dp = {}
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())

def Fib(n):
    a, b = 0, 1
    if n == 0:
        return a + 1
    elif n == 1:
        return b
    else:
        for i in range(n):
            a, b = b, a + b
        return b

print(Fib(n))

Python: # -*- coding: utf-8 -*-
"""
Created on Thu Mar 21 21:43:51 2019

@author: Yamazaki Kenichi
"""

s = int(input())
#T = [-1 for i in range(s+1)]
#T[0],T[1] = 1,1
#def fib(n):
#    if T[n] != -1:
#        return T[n]
#    else:
#        T[n] = fib(n-2) + fib(n-1)
#        return T[n]
#print(fib(s))

F = [1,1]
for i in range(s):
    F.append(F[-2]+F[-1])
print(F[s])

Python: n = int(input())

fib=[]

fib.append(1)
fib.append(1)

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

print(fib[n])

Python: # coding: utf-8
# Your code here!

def fibo(n, memo = {}):
   if n == 0 or n == 1:
      return 1
   elif n in memo:
      return memo[n]
   else:
      memo[n] = fibo(n - 1, memo) + fibo(n - 2, memo)
      return memo[n]

n = int(input())
print(fibo(n))

Python: n = int(input())
memo = [1, 1] + [0 for _ in range(n-1)]
for i in range(n+1):
    if not memo[i]:
        memo[i] = memo[i - 1] + memo[i - 2]
print(memo[-1])

Python: n = int(input())
if n < 2:
	ans = 1
else:
	a = [0] * (n+1)
	a[0] = a[1] = 1
	for i in range(2, n+1):
		a[i] = a[i-1] + a[i-2]
	ans = a[n]
print(ans)

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

Python: def fib_memo(n):
    memo = [-1]*(n+1)
    def fib(n):
        if n==0 or n==1:
            return 1
        if memo[n] != -1:
            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 mul(A,B):
    C=[[0]*len(B) for i in range(len(A[0]))]
    for i in range(len(A)):
        for j in range(len(B[0])):
            for k in range(len(B)):
                C[i][j]=(C[i][j]+A[i][k]*B[k][j])
    return C

def matpow(vec,n):
    B=[[0]*len(vec) for i in range(len(vec))]
    for i in range(len(vec)):
        B[i][i]=1
    while(n>0):
        if n&1:
            B=mul(B,vec)
        vec=mul(vec,vec)
        n>>=1
    return B

N=int(input())
vec=[[1,1],[1,0]]

vec=matpow(vec,N+1)
print(vec[1][0])

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: # ALDS_10_A - フィボナッチ数

n = int(input())

dp = [0] * (n + 1)

for i in range(n + 1):
    if (i == 0) or (i == 1):
        dp[i] = 1
    else:
        dp[i] = dp[i - 1] + dp[i - 2]

print(dp[-1])
# print(dp)

Python: def main():
    def fib(n):
        a = 1
        b = 1
        if n == 0:
            return a
        elif n == 1:
            return b
        else:
            for i in range(n-1):
                a, b = b, a + b
            return b
    
    n = int(input())
    print(fib(n))
        
if __name__ == '__main__':
    main()

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: import sys
n = int(input())
if n < 2:
    print(1)
    sys.exit()
a, b = 1, 1
for i in range(n-1):
    c = a + b
    a = b
    b = c
print(c)

Python: n = int(input())

A = [1]*(n+1)

for i in range(2, n+1):
    A[i] = A[i-1] + A[i-2]
    
print(A[-1])