#include<iostream>
#include<string>
#include<algorithm>
#include <vector>
#include <cstdio>
#include <cmath>
#include <set>
#include <cstring>
#include <string>
#include <sstream>
using namespace std;
int main()
{
    long long a,b,c,d,e;
    cin >> a;
    b = a / 1000;
    c = b / 3600;
    d = b % 3600 / 60;
    e = b % 3600 % 60;
    c %= 24;
    if (c < 10)cout << "0";
    cout << c << ":";
    if (d < 10)cout << "0";
    cout << d << ":";
    if (e < 10)cout << "0";
    cout<< e;
    return 0;
}

#include <bits/stdc++.h>

using namespace std;
const int t = 105;

int a[t][t];

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

    int left = 0, right = m - 1, top = 0, bottom = n - 1;
    int k = 1;
    while (left <= right && top <= bottom) 
    {
        for (int i = left ; i <= right; i ++) {
            a[top][i] = k ++;
        }
        for (int i = top + 1; i <= bottom; i ++) {
            a[i][right] = k ++;
        }
        for (int i = right - 1; i >= left && top < bottom; i --) {
            a[bottom][i] = k ++;
        }
        for (int i = bottom - 1; i > top && left < right; i --) {
            a[i][left] = k ++;
        }
        left ++, right --, top ++, bottom --;
    }
    for (int i = 0; i < n; i ++) 
    {
        for (int j = 0; j < m; j ++) 
        {
            cout << a[i][j] << " ";
        }
        cout << endl;
    }
    return 0;
}

class Solution
{
  public:
    vector<int>findNumbersWithSum(vector<int>&nums,int target)
    {
      unordered_set<int> us;
      for(int a:nums)
      {
        if(us.count(target-a))return vector<int>({target-a,a});
        us.insert(a);
      }
    }
};

class Solution {
public:
    vector<int> getLeastNumbers_Solution(vector<int> input, int k) {
        sort(input.begin(),input.end());
        vector<int>res;
        for(int i=0;i<k;i++)res.push_back(input[i]);
        return res;
    }
};

class Solution {
public:
    int getNumberOfK(vector<int>& nums , int k) {
        int a=0;
        for(int c:nums)
          if(c==k)a++;
        return a;
    }
};

class Solution 
{
public:
int a=0;
    int getSum(int n) 
    {
        if(n<1)return a;
        a+=n;
        n--;
        return getSum(n);

    }
};    

class Solution
{
public:
    string replaceSpaces(string &str) {
        string res;
        for (auto x : str)
            if (x == ' ')
                res += "%20";
            else
                res += x;
        return res;
    }
};

class Solution {
public:
    int Fibonacci(int n) {
        if (n == 0)
            return 0;
        else if (n == 1)
            return 1;
        else if (n == 2)
            return 1;
        else
            return Fibonacci(n - 1) + Fibonacci(n - 2);
    }
};

#include<iostream>
using namespace std;
int n,m;
int cnt=0;
int dfs(int x,int y)
{
    if(x==n&&y==m) cnt++;
    else
    {
        if(x<n) dfs(x+1,y);
        if(y<m) dfs(x,y+1);
    }
}
int main()
{
    cin>>n>>m;
    dfs(0,0);
    cout<<cnt;
}

#include<iostream>
using namespace std;
int a,b;
void f(int k)
{
    if(k==a)b++;
    else if(k<a)
    {
        f(k+1);
        f(k+2);
    }
}
int main()
{

    cin>>a;
    f(0);
    cout<<b;
    return 0;
}