Go: package main

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

//util
var sc = bufio.NewScanner(os.Stdin)

func nextStr() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list {
		buf.Write([]byte(fmt.Sprintf(" %d", v)))
	}
	buf.Write([]byte("\n"))
	buf.Flush()
}

//solve
//単純な場合
func fibonacci_(n int) int {
	if n == 0 || n == 1 {
		return 1
	}
	return fibonacci_(n-2) + fibonacci_(n-1)
}

//メモ再帰の利用
func fibonacci(n int) int {
	if n == 0 || n == 1 {
		F[n] = 1
	}
	//F[n]が計算済みの場合
	if F[n] > 0 {
		return F[n]
	}
	F[n] = fibonacci(n-2) + fibonacci(n-1)
	return F[n]
}

const MAX = 50

var F [MAX]int

func main() {
	sc.Split(bufio.ScanWords)
	n := nextInt()
	fmt.Println(fibonacci(n))

}

C++: // DP(???????¨??????? Dynamic Programing)
// ????????±???????????¢???
// ?????£??????????????°???
// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_10_A

#include <iostream>
using namespace std;

#define MAX_N 44

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

int n;
int fib(int);

int main()
{
    cin >> n;
    for(int i=0;i<MAX_N+1;++i)
        Memo[i].flg=false;
    cout << fib(n) << endl;
    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 <iostream>

using namespace std;

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

C++: #include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <unordered_map>
#include <vector>
#include <string.h>
#include <set>

using namespace std;

#define COUT(x) cout << #x << " = " << (x) << " (L" << __LINE__ << ")" << endl

template<class T> void printvec(const vector<T>& v) {
  for (auto x : v) { cout << x << " "; }
  cout << endl;
}
template<class T> void printtree(const vector< vector<T> >& tree) {
  for (long long i = 0; i < tree.size(); ++i) {
    cout << i + 1 << ": "; printvec(tree[i]);
  }
}
template<class T, class U> void printmap(const map<T, U>& mp) {
  for (auto x : mp) { cout << x.first << "=>" << x.second << endl; }
}

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }

#define rep(i, n) for(ll i = 0; i < n; ++i)
#define all(s) s.begin(), s.end()
#define sz(x) (ll)(x).size()
#define fr first
#define sc second
#define mp make_pair
#define pb push_back
#define eb emplace_back

typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> P;
typedef tuple<ll, ll, ll> triple;
typedef double D;
typedef vector<ll> vl;
typedef vector<P> vp;

const ll INF = 1e9;
const ll MOD = 1000000007;  // 1e9 + 7

int main(int argc, char** argv) {
  cin.tie(NULL);
  cout.tie(NULL);
  ios_base::sync_with_stdio(false);
  //cout << setprecision(10) << fixed;

  ll n;
  cin >> n;
  vector<ll> dp(n+1);
  dp[0] = 1;
  dp[1] = 1;
  rep(i,n-1) {
    dp[i+2] = dp[i+1] + dp[i];
  }
  cout << dp[n] << endl;
}

C++: #include <iostream>
#include <string>
#include <stdio.h>

using namespace std;

long long dpfibo(int n){
    long long F[44];
    F[0] = F[1] = 1;
    if(n == 0 or n == 1) return 1;
    for(int i = 2; i <= n; ++i){
        F[i] = F[i-1] + F[i-2];
    }
    return F[n];
}

int main(){
    int n;
    scanf("%d", &n);
    cout << dpfibo(n) << endl;
    return 0;
}

C++: #include<iostream>
#include<iomanip>
#include<vector>
#include<string>
#include<string.h>
#include<math.h>
#include<utility>
#include<algorithm>
#include<functional>
using namespace std;
 
int n;
int s=0;
int a[45];

 
int main()
{
	cin>>n;

	if(n==0 || n==1){
		cout<<1<<endl;
		return 0;
	}
	a[0]=1;
	a[1]=1;

	for(int i=1;i<n;i++){
	s=a[i]+a[i-1];
	a[i+1]=s;
	}

	cout<<s<<endl;

    return 0;
}

C++: #include <iostream>
int F[100]; // ???????????????
int main() 
{
int n;
F[0] = 1;
F[1] = 1;
for (int i=2; i<45; ++i) 
{ // ???????????????
F[i] = F[i-2]+F[i-1];
}
cin>>n;
cout<<F[n];
}

C++: #include<iostream>
#include<vector>

using namespace std;

int main() {
	int n;
	cin >> n; 
	vector<int> v;
	v.push_back(1);
	v.push_back(1);
	for (int i = 2; i <= n; i++) v.push_back(v[i - 1] + v[i - 2]);
	cout << v[n] << endl;
}

C++: #include <iostream>
#include <iomanip>
#include <algorithm>
#include <vector>
#include <string>
#include <queue>
#include <stack>
#include <functional>
#include <complex>
#include <cmath>
#include <ccomplex>
using namespace std;

int main() {
	int n;
	cin >> n;

	int dp[50];
	dp[0] = 1;
	dp[1] = 1;

	for (int i = 2; i < 45; i++) {
		dp[i] = dp[i - 1] + dp[i - 2];
	}
	cout << dp[n] << endl;
}

C++: #include <iostream>
#include <stdlib.h>

using namespace std;

int Fib(int n){

	int fib = 0;

	if(n == 0 || n == 1){
		return 1;
	}

	fib = Fib(n-1)+Fib(n-2);

	return fib;
}

int main(){

	int n;

	cin >> n;

	cout << Fib(n) << endl;

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define MAX 100

int dp[MAX];

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

int main() {
  int ans, n;
  cin >> n;

  for (int i = 0; i <= n; i++) {
    dp[i] = 0;
  }

  ans = fib(n);

  cout << ans << endl;
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define repR(i, n) for(int i = (n) - 1; i > -1; i--)
#define rep1(i, n) for(int i = 1; i < (int)(n + 1); i++)
#define rep1R(i, n) for(int i = (n); i > 0; i--)
using namespace std;

int F[50] = {};

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

int main() {
  int N;
  cin >> N;
  cout << fibonacci(N) << endl;
  return 0;
}

C++: #include <algorithm>
#include <cmath>
#include <cstdio>
#include <deque>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>

using namespace std;

typedef long long ll;

#define MOD 1000000007

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

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

int main(int argc, char const *argv[])
{
    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 <bits/stdc++.h>
using namespace std;
#define MAX 44
int fibonacci(int);
int F[MAX];

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

int fibonacci(int n){
  if(n == 0 || n == 1){
    return F[n] = 1;
  }
  return F[n] = fibonacci(n-2) + fibonacci(n-1);
}

C++: #include <iostream>

using namespace std;

int fib(int n);

int memo[45];
int main() {
  int n;

  //入力
  cin >> n;

  // 出力
  cout << fib(n) << endl;

  return 0;
}

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