ШВБ_N2_перебор

#include <iostream>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#include <stack>
#include <set>
#include <map>
#define pii pair <int,int>
#define vec vector
using namespace std;
using ll = long long;
using ld = long double;
using db = double;
void cv(vector <int> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}

void cvl(vector <ll> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}


void cvv(vector <vector <int> > &v){
    for (auto x: v) cv(x);
    cout<<"\n";
}

void cvb(vector <bool> v){
    for (bool x: v) cout<<x<<' ';
    cout<<"\n";
}

void cvs(vector <string>  v){
    for (auto a: v){
        cout<<a<<"\n";
    }
}


vector <int> to(int x, int bs){
    vector <int> r;
    while (x>0){
        r.push_back(x % bs);
        x/=bs;
    }
    reverse(r.begin(), r.end());
    return r;
}



int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n;
    cin>>n;
    vector <int> s;
    int ans=0;
    bool ok;
    for (int i=0;i<pow(25, n); ++i){
        s = to(i, 25);
        if (s.size() != n) continue;
        s = to(i,5);
        //cv(s);
        ok=1;
        for (int j = 0;j<s.size();++j){
            if (s[j] % 2 == 1){
                ok=0;
                break;
            }
        }
        if (ok) {
                ans++;
        }
    }
    cout<<ans;
}