Go: package main

import (
	"bufio"
	"io"
	"os"
	"strconv"
	"fmt"
)

var (
	nstr   func() string
	stdout *bufio.Writer
)

func init() {
	nstr = newReadString(os.Stdin)
	stdout = bufio.NewWriter(os.Stdout)
}

func main() {
	defer stdout.Flush()
	n := nint()
	r := fibonacci(n)
	fmt.Println(r)
}

func fibonacci(n int) int{
	if n == 0 || n == 1{
		return 1
	}else{
		fiList := make([]int, n+1)
		fiList[0] = 1
		fiList[1] = 1
		for i:=2; i<n+1; i++{
			fiList[i] = fiList[i-1] + fiList[i-2]
		}
		return fiList[n]

	}

}

func newReadString(ior io.Reader) func() string {
	r := bufio.NewScanner(ior)
	r.Buffer(make([]byte, 1024), int(1e+11))
	r.Split(bufio.ScanWords)

	return func() string {
		if !r.Scan() {
			panic("Scan failed")
		}
		return r.Text()
	}
}

func nint64() int64 {
	i, err := strconv.ParseInt(nstr(), 0, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

func nint() int {
	return int(nint64())
}

func getIntSlice(n int) []int {
	b := make([]int, n)
	for i := 0; i < n; i++ {
		b[i] = nint()
	}
	return b
}

func getStringSlice(n int) []string {
	b := make([]string, n)
	for i := 0; i < n; i++ {
		b[i] = nstr()
	}
	return b
}

func gcd(x, y int) int {
	if y == 0 {
		return x
	}
	return gcd(y, x%y)
}

func lcm(x, y int) int {
	return x * y / gcd(x, y)
}

func contains(s []int, e int) bool {
	for _, a := range s {
		if a == e {
			return true
		}
	}
	return false
}

func bin(i int, prefix bool) string {
	i64 := int64(i)

	if prefix {
		return "0b" + strconv.FormatInt(i64, 2)
	} else {
		return strconv.FormatInt(i64, 2)
	}
}

func strReverse(s string) string {
	runes := []rune(s)
	for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
		runes[i], runes[j] = runes[j], runes[i]
	}

	return string(runes)
}

C++: #include<iostream>
#include<algorithm>
#include<cmath>
#include<vector>
#include<string>
using namespace std;
int main()
{
  int n;
  cin>>n;
  int dp[45];
  dp[0]=dp[1]=1;
  for(int i=2;i<=45;i++) dp[i]=dp[i-1]+dp[i-2];

  cout<<dp[n]<<endl;
}

C++: #include<cstdio>
using namespace std;

int fib(int n);

int main() {
	int n;
	scanf("%d", &n);
	printf("%d\n", fib(n));
	return 0;
}

int fib(int n) {
	if (n == 0 || n == 1)return 1;
	else return fib(n - 1) + fib(n - 2);
}

C++: #include "bits/stdc++.h"
using namespace std;
int d;
int dd[50];
int fib(int a){
	if(a==0||a==1)return dd[a]=1;
	if(dd[a]!=-1)return dd[a];
	return dd[a]=fib(a-1)+fib(a-2);
}

int main() {
int c;
cin>>c;
for (int i = 0; i < 50; ++i) {
	dd[i]=-1;
}

cout<<fib(c)<<endl;
	return 0;
}

C++: #include <iostream>
using namespace std;

#define MAX_N 44

struct memo{
    int num;
    bool flg=false;
}Memo[MAX_N+1];

int n;
int fib(int);

int main()
{
    cin >> n;
    cout << fib(n);
    return 0;
}

int fib(int m){
    if(m == 0){
        if(!Memo[0].flg){
        Memo[0].num=1;
        Memo[0].flg=true;
        }
        return 1;
    }
    if(m == 1){
        if(!Memo[1].flg){
        Memo[1].num=2;
        Memo[1].flg=true;
        }
        return 1;
    }

    if(Memo[m].flg){
        return Memo[m].num;
    }
    else{
        Memo[m].num=fib(m-1) + fib(m-2);
        Memo[m].flg=false;
        return fib(m-1) + fib(m-2);
    }
}

C++: #include <bits/stdc++.h>
#define REP(i,n) for (int i = 0; i <(n); ++i)
#define REP2(i,x,n) for (int i = x; i <(n); ++i)
#define ALL(v) v.begin(), v.end()
#define RALL(v) v.rbegin(), v.rend()
using namespace std;
using ll = long long;
using P = pair<int,int>;
static const double PI = acos(-1);
static const int INF = 1e9+7;


/*
DP
フィボナッチ数列

*/

int main(){

  int n;
  cin >> n;
  int fib[n+1];
  fib[0] = 1;
  fib[1] = 1;
  REP2(i,2,n+1){
    fib[i] = fib[i-1] + fib[i-2];
  }

  cout << fib[n] << endl;
  return 0;
}

C++: #include<stdio.h>

int dp[50];

int fib(int n) {
  if ( n == 0 || n == 1 ) return dp[n] = 1;
  if ( dp[n] != -1 ) return dp[n];
  return dp[n] = fib(n - 1) + fib(n - 2);
}

int main() {
  int n, i;
  for ( i = 0; i < 50; i++ ) dp[i] = -1;

  scanf("%d", &n);
  printf("%d\n", fib(n));

  return 0;
}

C++: #include<iostream>
using namespace std;

int main()
{
	int n,i;
	int a[44];
	cin >> n;
	a[0]=1;
	a[1]=1;
	for(i=2;i<n;i++){
		a[i]=a[i-1]+a[i-2];
	}
	cout << a[n-1]<<endl;

}

C++: #include <bits/stdc++.h>
using namespace std;
#define Rep(i, n) for (int i = 0; i < (int)(n); i++)
#define BitRep(i, n) for (int i = 0; i < (int)(1 << n); i++)
#define Sum(vec) accumulate(vec.begin(), vec.end(), 0)
#define Sort(vec) sort(vec.begin(), vec.end())
#define Reverse(vec) reverse(vec.begin(), vec.end())
#define Next_permutation(vec) next_permutation(vec.begin(), vec.end())

int main() {
    int n;
    cin >> n;
    int F[50];
    F[0] = F[1] = 1;
    for (int i = 2; i <= n; i++) {
        F[i] = F[i - 1] + F[i - 2];
    }
    cout << F[n] << endl;
    return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>
#define rep(i, n) for(int i = 0; i < n; i++)
#define REP(i, m, n) for(int i = m; i < n; i++)
typedef long long ll;
using namespace std;

int main() {
    int n ;
    cin >> n;
    int dp[50];
    for(int i = 0; i <= n; i++) dp[i] = 0;
    dp[0] = 1;
    dp[1] = 1;
    for(int i = 2; i <= n; i++){
        dp[i] = dp[i-1] + dp[i-2];
    }
    cout << dp[n] << endl;

    return 0;
}