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 <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

int N;
int memo[50];

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

int main(void) {

    cin >> N;

    for (int i = 0; i < 50; ++i) memo[i] = -1;

    cout << fibo(N) << endl;

    return 0;
}

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

typedef long long ll;
typedef pair<ll, ll> P;

const ll mod =  1000000007;  //出力は (ans % mod + mod) % mod  (負の剰余を正にする)
const int inf = 1e9;
const long long INF = 1LL << 60;   // INF = 11

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

C++: #include <iostream>
#define rep(i,a) for(int i=0;i<(a);++i)

int fib[45];
int n;

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

  fib[0] = fib[1] = 1;
  rep( i, n-1 )
    fib[i+2] = fib[i] + fib[i+1]; 

  std::cout << fib[n] << std::endl;

  return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
#define SIZE 200005
#define INF 1000000005LL
#define MOD 1000000007

using namespace std;
typedef long long int ll;
typedef pair <int,int> P;

int n;
int a[50];


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

  return 0;
}

C++: #include<cstdio>
#define MAX 45
int F[MAX];

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

int main()
{
	int n;
	scanf("%d", &n);

	printf("%d\n", fibonacci(F,n));

	return 0;
}

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

using namespace std;

int main()
{
        int n;
        cin >> n;
        if (n <= 1) {
                cout << 1 << endl;
                return 0;
        }

        int *fib = new int[n + 1];
        fib[0] = fib[1] = 1;
        for (int i = 2; i <= n; i++) {
                fib[i] = fib[i - 1] + fib[i - 2];
        }
        cout << fib[n] << endl;
        delete [] fib;

        return 0;
}

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

#define N_MAX 45

int table[N_MAX];

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

int main()
{
	for(int i=0; i<N_MAX; i++) table[i] = 0;
	
	int n;
	cin >> n;
	cout << fib(n) << endl;

	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define rep(i,N) for(ll i=0;i<N;++i)
typedef long long int ll;
ll INF = 1LL<<60;

// フィボナッチ数列の第n項の出力
ll dp[1010];

int main(){
    ll 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;
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <map>
using namespace std;
typedef long long int ll;

ll a[50];

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

C++: #include"iostream"
using namespace std;
int n;
int main()
{
	cin >> n; 
	if (n == 1 || n == 0){
		cout << 1 << endl;
	}
	long long a=1, b=1,c;
	for (int i = 1; i < n; i++)
	{
		c = a + b;
		a = b;
		b = c;
	}
	cout << c << endl;
	return 0;
}

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

int main(){
    int n;
    int F[50];
    cin >> n;
    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<algorithm>
#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;

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

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

    cout << fibonacci(n) << endl;

    return 0;
}

C++: // -*- mode:c++; coding:utf-8; c-basic-offset:2; -*-
// ALDS1_10_A: Fibonacci Number

#include <algorithm>
#include <cstdio>

#define NDEBUG
#include <cassert>

class Fibonnacci {
  static const unsigned int N = 44u;
  unsigned int n_;
  unsigned long* f_;

public:
  Fibonnacci(unsigned int n = N) : n_(std::max(1, n))
  {
    f_ = new unsigned long[n_+1];
    f_[0] = f_[1] = 1;
    for (auto i = 2u; i <= n; ++i) {
      f_[i] = f_[i-1] + f_[i-2];
    }
  }

  ~Fibonnacci() { delete[] f_; }
  
  unsigned long operator () (unsigned int n) const
  {
    assert(n <= n_);
    return f_[n];
  }
};

int main()
{
  unsigned int n;
  std::scanf("%u", &n);
  Fibonnacci fib;
  std::printf("%lu\n", fib(n));
}

// eof