Go: package main

import "fmt"

func main() {
	var n int
	fmt.Scan(&n)

	x, y := int64(0), int64(1)
	for i := 0; i < n; i++ {
		x, y = y, x+y
	}

	fmt.Println(x)
}

C++: #include <iostream>

using namespace std;

int _fib(int n, int target, int last, int last2) {
  if (n == target)
    return last + last2;
  else
    return _fib(n + 1, target, last + last2, last);
}

int fib(int n) {
  if (n == 0 or n == 1)
    return 1;
  else
    return _fib(2, n, 1, 1);
}

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

C++: #include <iostream>

using namespace std;

#define INF -1

int dp[45];

int main()
{
	for(int i = 0; i < 45; i++) { dp[i] = INF; }

	int n;

	cin >> n;

	dp[0] = 1;
	dp[1] = 1;

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

	cout << dp[n] << endl;

	return 0;
}

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

int memoization[45] = {0};

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

int main(int argc, char **argv) {
  ios_base::sync_with_stdio(false);
  memoization[0] = 1;
  memoization[1] = 1;
  int n;
  cin >> n;
  cout << fib(n) << endl;
  return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
using namespace std;
using ll = long long;
using P = pair<int, int>;
const int INF = 1001001001;
const int MOD = 1000000007;

template <typename T>
void print(const T &v);

int main()
{
    int n;
    cin >> n;
    vector<int> f = {1, 1};
    for (int i = 2; i <= n; i++)
    {
        f.push_back(f[i - 2] + f[i - 1]);
    }
    cout << f[n] << endl;
    return 0;
}

// Use For Debug
template <typename T>
void print(T const &v)
{
    for (int i = 0; i < v.size(); i++)
    {
        if (i)
            cout << ' ';
        cout << v[i];
    }
    cout << endl;
}

C++: #include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(ri,n) for(int ri = (int)(n-1); ri >= 0; ri--)
#define rep2(i,x,n) for(int i = (int)(x); i < (int)(n); i++)
#define repit(itr,x) for(auto itr = x.begin(); itr != x.end(); itr++)
#define rrepit(ritr,x) for(auto ritr = x.rbegin(); ritr != x.rend(); ritr++)
#define ALL(n) begin(n), end(n)
using ll = long long;
using namespace std;

int fib(int n){
  static vector<int> dp(45, -1);
  if(dp.at(n) != -1) return dp.at(n);
  if(n == 0 || n == 1) return dp.at(n) = 1;
  else return dp.at(n) = fib(n-1) + fib(n-2);
}

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

C++: #include <stdio.h>

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

C++: #include<bits/stdc++.h>
using namespace std;
#define ll long long 
#define rep(i,n) for(ll i=0;i<n;i++)
#define inf 999999999
const int mod = 1000000007;
ll cnt = 0;


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

}

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


int main(){
	int n;
	scanf("%d", &n);
	int prev = 1;
	int prevprev = 1;
	int val;
	if (n == 0 || n == 1){
		val = 1;
	}
	else{
		for (int i = 1; i < n; i++){
			val = prev + prevprev;
			prevprev = prev;
			prev = val;
		}
	}
	printf("%d\n", val);

	return 0;
}

C++: #include<iostream>
using namespace std;
int dp[50];
int fibonacci(int x){
  if(x==0 || x==1) return 1;
  if(dp[x]!=0) return dp[x];
  return dp[x]=fibonacci(x-1)+fibonacci(x-2);
}
int main(){
  int n;
  cin>>n;
  cout<<fibonacci(n)<<endl;
  return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<string>
#include<sstream>
#include<cmath>
#include<numeric>
#include<map>
#include<stack>
#include<queue>
#include<list>
using namespace std;
int inf = 1000000000;

int main(void) {

  int n;
  cin >> n;
  vector<int> f(n+1);
  f[0] = 1;
  f[1] = 1;
  for(int i=2; i<=n; i++) f[i] = f[i-1] + f[i-2];
  cout << f[n] << endl;

  return 0;
}

// EOF

C++: #include <stdio.h>

int main() {
    int n;
    scanf("%d", &n);
    int F[50];
    F[0] = 1;
    F[1] = 1;
    for(int i=2; i<50; i++) F[i] = F[i-2] + F[i];
    
    printf("%d\n", F[n]);
    return 0;
}

C++: #include <iostream>

int main()
{
	int n; std::cin >> n;
	
	long long int* DP = new long long int[n+1];
	DP[0] = DP[1] = 1;
	for (int i=2; i<=n; i++) DP[i] = DP[i-1] + DP[i-2];
	
	std::cout << DP[n] << std::endl;
	
	delete[] DP;
	
	return 0;
}

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

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

C++: #include <algorithm>
#include <cassert>
#include <climits>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <string>
#include <vector>

#define all(x) begin(x), end(x)

using namespace std;

template <typename T> T gcd(T a, T b) {
  if (a % b == 0) {
    return b;
  } else {
    return gcd(b, a % b);
  }
}

template <typename T> T lcm(T a, T b) { return a * b / gcd(a, b); }

int dp[45] = {0};
int fib(int n) {
    if (n == 0 || n == 1) {
        return 1;
    }
    if (dp[n-1] != 0) {
        if (dp[n-2] != 0) {
            return dp[n-1] + dp[n-2];
        }
    }
    dp[n-1] = fib(n-1);
    dp[n-2] = fib(n-2);
    return dp[n-1] + dp[n-2];
}

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

C++: /*
    ????????°??§???????????¨????????????
*/

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <limits.h>
#include <float.h>
#include <iostream>
#include <algorithm>
#include <string>
#include <iterator>
#include <vector>
#include <map>
#include <utility>
#define LLU unsigned long long int
#define LL long long int
#define LD long double
using namespace std;
#define Lfmax DBL_MAX
#define LLUmax ULLONG_MAX
#define LLmax LLONG_MAX
#define dmax INT_MAX
#define vd vector<int>
#define vLL vector<long long int>
#define vLLU vector<unsigned long long int> 
#define pb push_back
#define mp make_pair
#define fi first
#define sec second
#define debug printf("asd\n")
#define debugd(a) printf("--%d\n",a)
#define debugdd(a,b) printf("--%d %d\n",a,b)
#define debugarr(a,b) for(int i=0 ; i<b ; i++)printf("%d ",a[i]);printf("\n")
#define newline printf("\n")
#define forin(a,b,c) for(int a=b ; a<c ; a++)
#define forde(a,b,c) for(int a=b ; a>=c ; a--)


inline void scd(int &a){scanf("%d",&a);}
inline void scdd(int &a,int &b){scanf("%d %d",&a,&b);}
inline void sctd(int &a,int &b,int &c){scanf("%d %d %d",&a,&b,&c);}
inline void scdlld(LL &a,LL &b){scanf("%I64d %I64d",&a,&b);}
inline void sclld(LL &a){scanf("%I64d",&a);}

#define scarrd(a,b) for(int index=0 ; index<b ; index++)scanf("%d",&a[index])
#define prdlld(a,b) printf("%I64d %I64d",a,b)
#define prdd(a,b) printf("%d %d",a,b)
#define prd(a) printf("%d",a)
#define prarr(a,b) for(int i=0 ; i<b ; i++)printf("%d ",a[i])
#define iniarr(a,b) for(int i=0 ; i<b ;i++)a[i]=0
#define arr(a,b) int *a=(int *)malloc(b*sizeof(int))
#define llarr(a,b) long long int *a=(long long int *)malloc(b*sizeof(long long int))
#define st(a,b) char *a=(char *)malloc(b*sizeof(char))
#define grav 9.8
#define pi 3.14159265

int fbc[200000];

int fb(int a)
{
	if(fbc[a]>0)
	return fbc[a];
	
	
	if(a<2)
	return 1;
	
	fbc[a]=fb(a-1)+fb(a-2);
	return fbc[a];
	
}

int main()
{
	iniarr(fbc,200000);
	int a;
	scd(a);
	printf("%d\n",fb(a));	
	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
    vector<int> dp;
    dp.push_back(1),dp.push_back(1);
    for(int i=0;i<44;i++)dp.push_back(dp[i]+dp[i+1]);
    int N;scanf("%d",&N);
    printf("%d\n",dp[N]);
    return 0;
}