Go: package main

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

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

// func main(){
// 	sc := bufio.NewScanner(os.Stdin)
// 	sc.Scan()
// 	n, _ := strconv.Atoi(sc.Text())
// 	fmt.Println(fib(n))
// }

import (
	"fmt"
)

func main(){
	var n, pre1, pre2, now int
	fmt.Scan(&n)
	if n == 0 || n == 1{
		fmt.Println(1)
	} else {
		pre1, pre2 = 1, 1
		for i:=1; i<n; i++{
			now = pre1 + pre2
			pre2 = pre1
			pre1 = now
		}
		fmt.Println(now)
	}

}

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

unsigned long long ull[44];

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

C++: #include <stdio.h>
#define N 44

int Fib[N];

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

int main(){
  int n;

  scanf("%d",&n);
  fib(n);
  printf("%d\n",Fib[n]);

  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define fs first
#define sc second
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define ALL(A) A.begin(),A.end()
#define RALL(A) A.rbegin(),A.rend()
typedef long long ll;
typedef pair<ll,ll> P;
const ll mod=1000000007;
const ll LINF=1LL<<60;
const int INF=1<<30;
vector<int> f(500);
int fib(int n){
	if((n == 1) || (n == 0)){
		return 1;
	}
	else if(f[n] != 0){
		return f[n];
	}
	else{
		f[n] = fib(n - 1) + fib(n - 2);
		return f[n];
	}
}
int main(){
	int n;cin>>n;
	cout << fib(n) << endl;
	return 0;
	
}

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

using namespace std;

int main()
{
    int n;
    cin>>n;
    vector<int> f(n+1,0);
    f[0]=1;
    f[1]=1;

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

    return 0;
}

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

void makeFibonacci(int fib[]){
  fib[0] = 1;
  fib[1] = 1;
  for(int i=2; i<=44; i++){
    fib[i] = fib[i-1] + fib[i-2];
  }
}

int main(){

  int fib[45];
  makeFibonacci(fib);

  int n;
  scanf("%d", &n);
  printf("%d\n", fib[n]);

  return -1;
}

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++: #define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <iostream>
#include <list>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <string>
#include <vector>
#include <algorithm>
#include <utility>
#include <queue>
#include <iomanip>
#define INF 2147483647
 
using namespace std;


int fibo(int n)
{
	int a = 0;
	int b = 1;
	int ans;
	int i;

	if (n == 0 || n == 1) return (n);
	for (i = 2; i <= n; i++) {
		ans = a + b;
		a = b;
		b = ans;
	}
	return (ans);
}


int main(void)
{
	int n;

	cin >> n;
	cout << fibo(n + 1) << endl;

	return (0);
}

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

int fib(int n);

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

    return 0;
}

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

C++: #include <cstdio>

using namespace std;

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

int main() {
    int n;
    scanf("%d", &n);
    printf("%d\n", fibonacci(n));
}

C++: #include <iostream>
#include <vector>
#define eol '\n'
using namespace std;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  
  int n;
  cin >> n;

  vector<int> list(n+1,0);
  list[0] = list[1] = 1;
  

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

  cout << list[n] << eol;
  
  return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <list>
#include <functional>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <numeric>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <cctype>
#include <sstream>

#define rep(i, a) REP(i, 0, a)
#define REP(i, a, b) for(int i = a; i < b; ++i)
#define rrep(i, a) RREP(i, a, 0)
#define RREP(i, a, b) for(int i = a; i >= b; --i)
#define repll(i, a) REPLL(i, 0, a)
#define REPLL(i, a, b) for(ll i = a; i < b; ++i)
#define rrepll(i, a) RREPLL(i, a, 0)
#define RREPLL(i, a, b) for(ll i = a; i >= b; --i)

typedef long long ll;
typedef unsigned long long ull;
typedef std::pair<int, int> P;
typedef std::pair<int, P> PP;
const double PI = 3.14159265358979323846;
const double esp = 1e-9;
const int infi = (int)1e+9 + 10;
const ll infll = (ll)1e+18 + 10;

int n;
ll fib[50];

int main(){
	fib[0] = fib[1] = 1;
	REP(i, 2, 50)fib[i] = fib[i - 1] + fib[i - 2];

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

	return 0;
}

C++: #include <iostream>
using namespace std;
int fib(int n){
    if(n == 0 || n == 1)   return 1;
    else
        return fib(n - 1) + fib(n - 2);    
}

int main(void){
    int n;
    cin >> n;
    cout << fib(n) << 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 <bits/stdc++.h>
using namespace std;
#define MAX_N 100000
#define MAX_M 100000
const int INF = 1e9;

int fib(int n){
  vector<long long> dp(n+1);
  dp[0]=1;
  dp[1]=1;
  for(int i=2;i<=n;i++){
    dp[i]=dp[i-1]+dp[i-2];
  }
  return dp[n];
}

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

C++: #include <cstdio>

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

int main(){
	int n;
	scanf("%d", &n);
	printf("%d\n", fib(n));
	return 0;
}

C++: #include<iostream>
using namespace std;
const int MAX = 44;
int dp[MAX];
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;
	cin >> n;
	for (int i = 0; i <= MAX; i++)
		dp[i] = -1;
	cout << fib(n) << endl;}

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

using namespace std;
const int dx[]={1,0,-1,0,1,-1,-1,1,0};
const int dy[]={0,1,0,-1,1,1,-1,-1,0};
const int INF = 1e9+101;
const long long LINF = 1e18;
const double EPS = 1e-8;
#define pb push_back
#define mk make_pair
#define fr first
#define sc second
#define reps(i,j,k) for(int i = (j); i < (k); ++i)
#define rep(i,j) reps(i,0,j)
#define all(a) (a).begin(),(a).end()
#define MOD 1000000007
typedef long long ll;
typedef pair<int,int> Pii;
typedef pair<ll, ll> Pll;
typedef pair<Pii,int> P;
typedef vector<int> vi;
typedef vector<ll> vll;
template<class T>
ostream& operator<<(ostream &out, const vector<T> &v){
	out << "{";
	rep(i,v.size()){
		out << v[i] <<", ";
	}
	return out << "}" << endl;
}
int memo[50];
int solve(int l) {
    if(memo[l] != -1) return memo[l];
    if(l <= 1) return 1;
    return memo[l] = solve(l-1)+solve(l-2);
}
int main() {
    memset(memo,-1,sizeof(memo));
    int N;
    cin >> N;
    cout << solve(N) << endl;
    return 0;  
}

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

int F[100];
int main() {
  F[0] = 1;
  F[1] = 1;

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

  int N;
  cin >> N;
  cout << F[N]<<endl;
}

C++: #include<stdio.h>
int main(){
  int A[44]={},a,i;
  A[0]=1;
  A[1]=1;
  scanf("%d",&a);
  for(i=2;i<=a;i++){
    A[i]+=(A[i-1]+A[i-2]);
  }
  printf("%d\n",A[a]);
}

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;
  return 0;
}