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"
using namespace std;
typedef long long ll;

template <typename TYPE>
void print_vec(const vector<TYPE>& v){
	for(int i=0; i<v.size(); i++){
		cout << v[i] << " ";
	}
	cout << endl;
}

template <typename TYPE>
void print_vec2(const vector<vector<TYPE>>& v){
	for(int i=0; i<v.size(); i++){
		cout << "i=" << i << ":   ";
		for(int j=0; j<v[i].size(); j++){
			cout << v[i][j] << "   ";
		}
		cout << endl;
	}
}



int fib(int i, vector<int> &dp){
    if(dp[i] != -1) return dp[i];
    if(i == 0) return dp[i] = 1;//dpにメモしながら返す
    if(i == 1) return dp[i] = 1;
    return dp[i] = fib(i-1, dp) + fib(i-2, dp);

}
int main(){//
   int n;
   cin >> n;
   vector<int> dp(n+5, -1);

   cout << fib(n, dp) << endl;


}

C++: #include <iostream>

long long int Fibo(long long int n)
{
    if(n == 0 || n == 1) return 1;
    return Fibo(n-1) + Fibo(n-2);
}
int main(){
    long long int n;
    std::cin >> n;
    std::cout << Fibo(n) << std::endl;
    return 0;
}

C++: #include <iostream>
#include <cstdlib>
#define MAX 50
using namespace std;

void fib(int n){
  int a[MAX];
  for(int i=0;i<MAX;i++) a[i]=1;
  for(int i=2;i<=n;i++){        
    a[i]=a[i-1]+a[i-2];
  }  cout << a[n] << endl;
}

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

C++: #include <cstdio>

int fibo(int n, int *dp) {
    if (n == 0 || n == 1) return 1;
    if (0 < dp[n]) return dp[n];
    return dp[n] = fibo(n-1, dp) + fibo(n-2, dp);
}

int
main ()
{
    int n;
    int dp[50];
    for (int i=0; i<50; i++) dp[i] = -1;
    scanf("%d", &n);
    printf("%d\n", fibo(n, dp));
    return 0;
}

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

int f[50];

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

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

  cout << fibo(n) << endl;
  return 0;
}

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

int arr[46];

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

    else
        arr[n]=fib(n-1)+fib(n-2);
    return arr[n];

}


int main()
{
    arr[0]=1;
    arr[1]=1;

    for(int i=2;i<=44;i++)
    {
        arr[i]=-1;
    }


    int n;
    cin>>n;
    cout<<fib(n)<<endl;




    return 0;
}

C++: #if 0

#endif

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;

int F[100];

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

C++: #include "bits/stdc++.h"
#define Rep(i,n) for(int i=0;i<(int)(n);i++)
#define For(i,n1,n2) for(int i=(int)(n1);i<(int)(n2);i++)
#define REP(i,n) for(ll i=0;i<(ll)(n);i++)
#define RREP(i,n) for(ll i=((ll)(n)-1);i>=0;i--)
#define FOR(i,n1,n2) for(ll i=(ll)(n1);i<(ll)(n2);i++)
#define RFOR(i,n1,n2) for(ll i=((ll)(n1)-1);i>=(ll)(n2);i--)
#define all(a)  (a).begin(),(a).end()
#define IOS std::cin.tie(0),std::ios::sync_with_stdio(false)

namespace idaten {

	using namespace std;
	using ll = int_fast64_t;
	using ull = uint_fast64_t;
	using P = std::pair<int64_t, int64_t>;
	template<typename T1, typename T2> inline bool chmin(T1& a, T2 b) { if (a > b) { a = b; return 1; }return 0; }
	template<typename T1, typename T2> inline bool chmax(T1& a, T2 b) { if (a < b) { a = b; return 1; }return 0; }
	template<class Type>struct is_vector : std::false_type {};
	template<class ValueType, class Alloc>struct is_vector<std::vector<ValueType, Alloc>> : std::true_type {};
	template <typename T> inline std::ostream& operator << (std::ostream& out, const std::vector<T>& v) {
		if (v.empty())return out;
		constexpr bool is_vector_v = is_vector<T>::value;
		if (is_vector_v)for (auto itr = v.begin(); itr != v.end();)out << (*itr), out << ((++itr != v.end()) ? "\n" : "");
		else for (auto itr = v.begin(); itr != v.end();)out << (*itr), out << ((++itr != v.end()) ? " " : "");
		return out;
	}
	inline void put() {}
	template<class T> inline void put(const T& first) { std::cout << first << "\n"; }
	template<class T, class... N> inline void put(const T& first, const N& ... rest) { std::cout << first << " "; put(rest...); }
	inline void putn() {}
	template<class T, class... N> inline void putn(const T& first, const N& ... rest) { std::cout << first << "\n"; putn(rest...); }

	void solve() {
		IOS;
		ll n;
		cin >> n;
		vector<ll> dp(n + 1, 0);
		dp[0] = dp[1] = 1;
		FOR(i, 1, n) {
			dp[i + 1] = dp[i] + dp[i - 1];
		}
		put(dp[n]);
	}
} // namespace idaten

int main() {
	idaten::solve();
	return 0;
}

C++: #include <cstdio>
#include <algorithm>
using namespace std;
int n,dp[50];
int main()
{
	dp[0]=1;
	dp[1]=1;
	for(int i=2;i<=50;i++){
		dp[i]=dp[i-2]+dp[i-1];
	}
	scanf("%d",&n);
	printf("%d\n",dp[n]);
	return 0;
}

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

int main(void){
  int n;
  int fib[45];
  fib[0] = 1;
  fib[1] = 1;

  cin >> n;

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

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

C++: #include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<ll, ll>;
constexpr int INF = 1001001001;
constexpr int MOD = 1000000007;

int main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);

  int n;
  cin >> n;

  int dp[100] = {};
  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 <stdio.h>
long long fiboDP(int n){
    long long fibodp[200]={0};
    fibodp[1]=1;
    fibodp[2]=1;
    for(int i=3;i<=n;i++){
        fibodp[i]=fibodp[i-1]+fibodp[i-2];
    }
    return fibodp[n];
}
int main(void){
    int n;
    scanf("%d",&n);
    printf("%lld\n",fiboDP(n+1));
   return 0;
}

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

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;

	cin >> n;
	cout << fib(n) << endl;

	return 0;
}