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
}

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


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

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

int fibans[44];
bool fibflag[44];

int fib(int n){
  if(n<2)return 1;
  if(fibflag[n] != true){
    fibans[n] = fib(n-1) + fib(n-2);
    fibflag[n] = true;
  }
  return fibans[n];
} 

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

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

int main(){
  
  int n, fib[50] = {1, 1};

  //recurrence relation of fibonacci number
  for(int i = 2;i < 45;i++) fib[i] = fib[i - 1] + fib[i - 2];

  //input and output
  cin >> n;
  cout << fib[n] << endl;
  
  return 0;
}

C++: #include <iostream>

int FibonacciNumber(int Index)
{
	if(Index == 0) return 1;
	if(Index == 1) return 1;
	return FibonacciNumber(Index - 1) + FibonacciNumber(Index - 2);
}

int main()
{
	int Index;
	std::cin >> Index;
	std::cout << FibonacciNumber(Index) << std::endl;
	return 0;
}

C++: #include <bits/stdc++.h>
//----***やべーやつら***----
using namespace std;
#define int long long

//----***型定義***----
using ll = long long;
using P = pair<int,int>;

//----***Like a Pythonista***----
#define REP(ii,jj,nn) for (ll ii=jj;ii<(nn);ii++)
#define RREP(ii,nn,jj) for (ll ii = nn; jj<ii;ii--)
#define each(i,...) for (auto&& i:__VA_ARGS__)
#define ALL(vec) (vec).begin(),(vec).end()
#define sum(...) accumulate(ALL(__VA_ARGS__),0LL)
#define dsum(...) accumulate(ALL(__VA_ARGS__),0.0)
#define vec(type,name,...) vector<type> name(__VA_ARGS__)
template<class T> inline auto max(const T& a){ return *max_element(ALL(a)); }
template<class T> inline auto min(const T& a){ return *min_element(ALL(a)); }
inline ll gcd(ll a,ll b){if(b == 0) return a;return  gcd(b,a%b);}
inline ll lcm(ll a,ll b){ll g = gcd(a,b);return a / g * b;}

//----***定数***----
#define MOD 1000000007
#define INF 100000000000000000
#define EPS 1e-9
const vector<vector<int>> DXY={{-1,0},{1,0},{0,-1},{0,1}};

//----***パーツ***----
#define fr first
#define se second

//----***入出力***---
#define print(out) cout<< out  << "\n";
#define debug(var)  do{std::cerr << #var << " ↓ "<<"\n";view(var);}while(0);
#define dbg cerr<<"🥺🥺🥺🥺🥺🥺"<<endl;
template<typename T> void view(T e){std::cout << e << std::endl;}
template<typename T> void view(const std::vector<T>& v){for(const auto& e : v){ std::cout << e << " "; } std::cout << std::endl;}
template<typename T> void view(const std::vector<std::vector<T> >& vv){ for(const auto& v : vv){ view(v); } }

//----***初期時読み込み***----
struct initial{initial(){cin.tie(0); ios::sync_with_stdio(0); cout<<fixed<<setprecision(15);};}initial_;

vector<int> memo(50,0);

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

}

signed main(){
  int N;cin>>N;
  memo[0]=memo[1]=1;
  int ans =fibo(N);
  print(ans)



}

C++: #include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)n;i++)
#define ll long long
using namespace std;

int dp[45];

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

    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;
}

C++: #include<iostream>
using namespace std;
#define MAX 45

int fib[45];
void make_fib(){
	fib[0] = 1;
	fib[1] = 1;
	for (int i=2;i<MAX;i++) {
	fib[i] = fib[i-1] + fib[i-2];
	}
}

int main() {
	int n;
	cin >> n;
	make_fib();
	cout << fib[n] << endl;
	return 0;
}

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


void fibonacci(int n){
  vector<int> fib;

  fib.push_back(1);
  fib.push_back(1);

  for(int i = 2;i < n;i++){
    fib.push_back(fib.at(i - 2) + fib.at(i - 1));
  }

  cout << fib.at(n - 1) << endl;

}

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

  return 0;
}

C++: #include <algorithm>
#include <cmath>
#include <deque>
#include <iostream>
#include <queue>
#include <string>
#include <numeric>
#include <vector>

using namespace std;

int memo[45] = {0};

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


int main() {
  int n;
  cin >> n;
  
  cout << fibo(n) << endl;

  return 0;
}

C++: #include<bits/stdc++.h>
#define INF 1e9
using namespace std;
int num[50];
int fib(int n){
    if(n==0 || n==1) return 1;
    else if(num[n]!=INF) return num[n];
    else return fib(n-1) + fib(n-2);
}
int main(){
    for(int i=0;i<50;i++) num[i]=INF;
    for(int i=0;i<45;i++){
        num[i]=fib(i);
    }
    int n;
    cin>>n;
    cout<<num[n]<<endl;
    return 0;
}

C++: #include <cstdio>

int main() {
	int n;
	int F[50];
	scanf("%d", &n);

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

	for (int i = 2; i <= n; i++) F[i] = F[i - 1] + F[i - 2];

	printf("%d\n", F[n]);
	return 0;
}

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

int main(){
  int n;
  cin >> n;
  int F[100];
  F[0] = 1;
  F[1] = 1;
  for(int i=2; i<n+1; i++){
    F[i] = F[i-2] + F[i-1];
  }
  cout << F[n] << endl;
}