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 <bits/stdc++.h>
#define _GLIBCXX_DEBUG
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rrep(i, n) for (int i = 1; i < (n+1); ++i)
using namespace std;
using ll = long long;
// const int INF = +100100100;
// typedef pair<int,int> P;



int main(){
    vector<int> a(50);
    a[0]=1;a[1]=1;
    for(int i = 2;i<45;++i){
        a[i]=a[i-1]+a[i-2];
    }
    int n;
    cin >> n;
    cout << a[n] << endl;
    return 0;
}

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

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

C++: #include<iostream>

using namespace std;

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

	cin >> n;

	cout << fib(n) << endl;

	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; n++){
        F[i]=F[i-1]+F[i-2];
    }
    
    cout << F[n] << endl;
    
    return 0;
}

C++: #include<bits/stdc++.h>

using namespace std;

int main()
{
	int n,fib[45];
	fib[0]=fib[1]=0;
	scanf("%d",&n);
	for(int i=2;i<=n;i++)
		fib[i]=fib[i-1]+fib[i-2];
	printf("%d\n",fib[n]);
	return 0; 
}

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

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

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

  printf("%d\n",fib[n]);
}

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

int fib[45];

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

    for (int i = 0; i <= N; i++)
    {
        if (i < 2)
        {
            fib[i] = 1;
        }
        else
        {
            fib[i] = fib[i - 2] + fib[i - 1];
        }
    }

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

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

int main() {
	int n;
	int i;
	vector<long long> fib;
	scanf("%d",&n);
	fib.resize(n+1);
	fib[0]=fib[1]=1;
	for(i=2; i<=n; ++i) {
		fib[i]=fib[i-1]+fib[i-2];
	}
	printf("%lld\n",fib[n]);
	return 0;
}

C++: #include <iostream>

using namespace std;

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

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>
#include <cstdlib>
#include <string>
#include <typeinfo>
#include <cstring>
#include <iostream>
#include <algorithm>
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;

typedef unsigned long long ull;
int dp[45] = {0};

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

int main(void) {
  int n;
  cin >> n;
  //cout << fib(n) << endl;
  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;
int fib(int n);
int main() {
  int n;

  //入力
  cin >> n;

  //出力
  cout << fib(n) << endl;

  return 0;
}

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

C++: #include <iostream>
#include <map>
using namespace std;
int memofib(int n) {
    static map<int,int> cache;
    map<int,int>::iterator it = cache.find(n);
    if( it != cache.cend() )
        return it->second;   
    int t;
    if(n==1) 
        return 1;
    else if(n==2)
        return 2;
    else
        return memofib(n-1) + memofib(n-2);
    cache.insert(std::make_pair(n, t));
    return t;
}
int main(void){
    int n;
    cin >> n ;
    cout << memofib(n) << endl;
    return 0;
}

C++: #include<iostream>
using namespace std;
int data[45];
int fib(int n){
  if(data[n]) return data[n];
  if(n==0||n==1) return data[n]=1;
  return data[n]=fib(n-1)+fib(n-2);
}
int main(){
  int n; cin>>n;
  cout<<fib(n)<<endl;
  return 0;
}

C++: #include<stdio.h>

int main(){
  int i,input,fibonacciA=1,fibonacciB=1,fibonacciC=1;
  scanf("%d",&input);
  if(input == 0 || input == 1){
    printf("%d\n",fibonacciA);
  }else{
    for(i=1;i<input;i++){
      fibonacciC = fibonacciB + fibonacciA;
      fibonacciA = fibonacciB;
      fibonacciB = fibonacciC;
    }
    printf("%d\n",fibonacciC);
  }
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define REP(i,s,n) for(int i=s;i<n;i++)
#define all(a) a.begin(),a.end()
typedef long long ll;
const double phi = (1 + sqrt(5)) / 2;
const double phi_ = (1 - sqrt(5)) / 2;
double fib(ll n){
    double res = pow(phi, n+1) - pow(phi_, n+1);
    return res / sqrt(5);
}
int main(){
    ll n, ans; cin >> n;
    ans = fib(n);
    cout << ans << endl;
    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 <cstdio>
#include <iostream>

using namespace std;

int F[50];

int fib(int n) {

	if (n == 0 || n == 1)
		return 1;
	if (F[n] != 0)
		return F[n];

	F[n] = fib(n - 1) + fib(n - 2);

	return F[n];
}

int main() {

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

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

	cout << fib(n) << endl;

	return 0;

}

C++: #include "stdio.h"

#define MAX 50
#define INIT -1

int dp[MAX];

int fibonacci(int n){
  if(n == 0 || n == 1){
    return dp[n] = 1;
  }

  if(dp[n] >= 0 ){
    return dp[n];
  }else{
    return dp[n] = fibonacci(n-1) + fibonacci(n-2);    
  }
}


int main(void){
  
  int N;
  scanf("%d", &N);
  
  for(int i=0;i<MAX;i++){
    dp[i] = INIT;
  }
    
  printf("%d\n", fibonacci(N));

  return 0;
}