Language: C++

#include <bits/stdc++.h>
#define pb push_back
#define IOS                                                                    \
  ios_base::sync_with_stdio(false);                                            \
  cin.tie(0);                                                                  \
  cout.tie(0)
#define ll long long int
#define ld long double
#define el '\n'
#define PI (ld)3.141592653589793238462643383279502884197169399375105820974944
#define inf (ll)1000000000
#define mod (ll)1000000007
#define mod1 (ll)998244353
#define fo(i, n) for (long long i = 0; i < int(n); i++)
#define pll pair<ll, ll>
#define ml map<ll,ll>
#define vli vector<pair<ll,int>>
#define vpl vector<pll>
#define vvl vector<vector<ll> >
#define vvpl vector< vector<pll> >
#define ff first
#define ss second
#define pqueue priority_queue< ll >
#define pdqueue priority_queue< ll,vl ,greater< ll > >
#define mem(a,b) memset(a,b,sizeof(a));
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define sz(a) (ll)a.size()
#define f(i,a,b) for(ll i=a;i<b;i++)
#define fd(i,a,b) for(ll i=a;i>=b;i--)
#define all(a) a.begin(),a.end()
#define vl vector<ll>
//#define x ff
//#define y ss
#define pt(a) for(auto it:a)cout<<it<<" ";cout<<endl;
unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
using namespace std;

double gcd(double a, double b) { return a < 0.01 ? b : gcd(fmod(b, a), a); }

vector<ll> parent, rak;

void make_set(int f){
    fo(i,f+1)parent.pb(i);
    rak.assign(f+1,1);
}

ll find_set(ll v) {
    if (v == parent[v])
        return v;
    return parent[v] = find_set(parent[v]);
}

ll union_sets(ll a, ll b) {
    a = find_set(a);
    b = find_set(b);
    if (a != b) {
        if (rak[a] < rak[b])
            swap(a, b);
        parent[b] = a;
        rak[a]+=rak[b];
        return (rak[a]-rak[b])*(rak[b]);
    }
    return 0;
}

long long bpow(long long a, long long b, long long m) {
  a %= m;
  long long res = 1;
  while (b > 0) {
    if (b & 1)
      res = res * a % m;
      a = a * a % m;
      b >>= 1;
  }
  return res;
}
ll extend_gcd(ll a,ll b,ll &x,ll &y){
    if(b==0){
        x=1;
        y=0;
        return a;
    }
    ll x1,y1;
    ll ans =extend_gcd(b,a%b,x1,y1);
    x=y1;
    y=x1-(a/b)*y1;

    return ans;
}
ll inverse(ll a,ll m){
    ll x,y;
    extend_gcd(m,a,x,y);
    y%=m;
    y+=m;
    y%=m;
    return y;
}

/*const int N = 1000001;
int lp[N+1];
vector<int> pr;
void s(){
for (int i=2; i<=N; ++i) {
        if (lp[i] == 0) {
            lp[i] = i;
            pr.push_back (i);
        }
        for (int j=0; j<(int)pr.size() && pr[j]<=lp[i] && i*pr[j]<=N; ++j)
            lp[i * pr[j]] = pr[j];
    }
}*/


ll kv;
ll t,n,x,y,h,k,z,p,q,w;
string s;
//vvl v;
//vl vis,d;

int main() {
    IOS;
    cin>>n;
    cout<<"Christmas ";
    n=25-n;
    while(n--)cout<<"Eve ";
    return 0;
}
#include <bits/stdc++.h>
#define pb push_back
#define IOS                                                                    \
  ios_base::sync_with_stdio(false);                                            \
  cin.tie(0);                                                                  \
  cout.tie(0)
#define ll long long int
#define ld long double
#define el '\n'
#define PI (ld)3.141592653589793238462643383279502884197169399375105820974944
#define inf (ll)1000000000
#define mod (ll)1000000007
#define mod1 (ll)998244353
#define fo(i, n) for (long long i = 0; i < int(n); i++)
#define pll pair<ll, ll>
#define ml map<ll,ll>
#define vli vector<pair<ll,int>>
#define vpl vector<pll>
#define vvl vector<vector<ll> >
#define vvpl vector< vector<pll> >
#define ff first
#define ss second
#define pqueue priority_queue< ll >
#define pdqueue priority_queue< ll,vl ,greater< ll > >
#define mem(a,b) memset(a,b,sizeof(a));
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define sz(a) (ll)a.size()
#define f(i,a,b) for(ll i=a;i<b;i++)
#define fd(i,a,b) for(ll i=a;i>=b;i--)
#define all(a) a.begin(),a.end()
#define vl vector<ll>
//#define x ff
//#define y ss
#define pt(a) for(auto it:a)cout<<it<<" ";cout<<endl;
unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
using namespace std;

double gcd(double a, double b) { return a < 0.01 ? b : gcd(fmod(b, a), a); }

vector<ll> parent, rak;

void make_set(int f){
    fo(i,f+1)parent.pb(i);
    rak.assign(f+1,1);
}

ll find_set(ll v) {
    if (v == parent[v])
        return v;
    return parent[v] = find_set(parent[v]);
}

ll union_sets(ll a, ll b) {
    a = find_set(a);
    b = find_set(b);
    if (a != b) {
        if (rak[a] < rak[b])
            swap(a, b);
        parent[b] = a;
        rak[a]+=rak[b];
        return (rak[a]-rak[b])*(rak[b]);
    }
    return 0;
}

long long bpow(long long a, long long b, long long m) {
  a %= m;
  long long res = 1;
  while (b > 0) {
    if (b & 1)
      res = res * a % m;
      a = a * a % m;
      b >>= 1;
  }
  return res;
}
ll extend_gcd(ll a,ll b,ll &x,ll &y){
    if(b==0){
        x=1;
        y=0;
        return a;
    }
    ll x1,y1;
    ll ans =extend_gcd(b,a%b,x1,y1);
    x=y1;
    y=x1-(a/b)*y1;

    return ans;
}
ll inverse(ll a,ll m){
    ll x,y;
    extend_gcd(m,a,x,y);
    y%=m;
    y+=m;
    y%=m;
    return y;
}

/*const int N = 1000001;
int lp[N+1];
vector<int> pr;
void s(){
for (int i=2; i<=N; ++i) {
        if (lp[i] == 0) {
            lp[i] = i;
            pr.push_back (i);
        }
        for (int j=0; j<(int)pr.size() && pr[j]<=lp[i] && i*pr[j]<=N; ++j)
            lp[i * pr[j]] = pr[j];
    }
}*/


ll kv;
ll t,n,x,y,h,k,z,p,q,w;
string s;
//vvl v;
//vl vis,d;

int main() {
    IOS;
    cin>>n;
    cout<<"Christmas ";
    n=25-n;
    while(n--)cout<<"Eve ";
    return 0;
}


Compiler output:
a.cc:162:10: error: redefinition of 'unsigned int seed'
  162 | unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
      |          ^~~~
a.cc:35:10: note: 'unsigned int seed' previously declared here
   35 | unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
      |          ^~~~
a.cc:165:8: error: redefinition of 'double gcd(double, double)'
  165 | double gcd(double a, double b) { return a < 0.01 ? b : gcd(fmod(b, a), a); }
      |        ^~~
a.cc:38:8: note: 'double gcd(double, double)' previously defined here
   38 | double gcd(double a, double b) { return a < 0.01 ? b : gcd(fmod(b, a), a); }
      |        ^~~
a.cc:167:12: error: redefinition of 'std::vector<long long int> parent'
  167 | vector<ll> parent, rak;
      |            ^~~~~~
a.cc:40:12: note: 'std::vector<long long int> parent' previously declared here
   40 | vector<ll> parent, rak;
      |            ^~~~~~
a.cc:167:20: error: redefinition of 'std::vector<long long int> rak'
  167 | vector<ll> parent, rak;
      |                    ^~~
a.cc:40:20: note: 'std::vector<long long int> rak' previously declared here
   40 | vector<ll> parent, rak;
      |                    ^~~
a.cc:169:6: error: redefinition of 'void make_set(int)'
  169 | void make_set(int f){
      |      ^~~~~~~~
a.cc:42:6: note: 'void make_set(int)' previously defined here
   42 | void make_set(int f){
      |      ^~~~~~~~
a.cc:174:4: error: redefinition of 'long long int find_set(long long int)'
  174 | ll find_set(ll v) {
      |    ^~~~~~~~
a.cc:47:4: note: 'long long int find_set(long long int)' previously defined here
   47 | ll find_set(ll v) {
      |    ^~~~~~~~
a.cc:180:4: error: redefinition of 'long long int union_sets(long long int, long long int)'
  180 | ll union_sets(ll a, ll b) {
      |    ^~~~~~~~~~
a.cc:53:4: note: 'long long int union_sets(long long int, long long int)' previously defined here
   53 | ll union_sets(ll a, ll b) {
      |    ^~~~~~~~~~
a.cc:193:11: error: redefinition of 'long long int bpow(long long int, long long int, long long int)'
  193 | long long bpow(long long a, long long b, long long m) {
      |           ^~~~
a.cc:66:11: note: 'long long int bpow(long long int, long long int, long long int)' previously defined here
   66 | long long bpow(long long a, long long b, long long m) {
      |           ^~~~
a.cc:204:4: error: redefinition of 'long long int extend_gcd(long long int, long long int, long long int&, long long int&)'
  204 | ll extend_gcd(ll a,ll b,ll &x,ll &y){
      |    ^~~~~~~~~~
a.cc:77:4: note: 'long long int extend_gcd(long long int, long long int, long long int&, long long int&)' previously defined here
   77 | ll extend_gcd(ll a,ll b,ll &x,ll &y){
      |    ^~~~~~~~~~
a.cc:217:4: error: redefinition of 'long long int inverse(long long int, long long int)'
  217 | ll inverse(ll a,ll m){
      |    ^~~~~~~
a.cc:90:4: note: 'long long int inverse(long long int, long long int)' previously defined here
   90 | ll inverse(ll a,ll m){
      |    ^~~~~~~
a.cc:241:4: error: redefinition of 'long long int kv'
  241 | ll kv;
      |    ^~
a.cc:114:4: note: 'long long int kv' previously declared here
  114 | ll kv;
      |    ^~
a.cc:242:4: error: redefinition of 'long long int t'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |    ^
a.cc:115:4: note: 'long long int t' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |    ^
a.cc:242:6: error: redefinition of 'long long int n'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |      ^
a.cc:115:6: note: 'long long int n' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |      ^
a.cc:242:8: error: redefinition of 'long long int x'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |        ^
a.cc:115:8: note: 'long long int x' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |        ^
a.cc:242:10: error: redefinition of 'long long int y'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |          ^
a.cc:115:10: note: 'long long int y' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |          ^
a.cc:242:12: error: redefinition of 'long long int h'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |            ^
a.cc:115:12: note: 'long long int h' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |            ^
a.cc:242:14: error: redefinition of 'long long int k'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |              ^
a.cc:115:14: note: 'long long int k' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |              ^
a.cc:242:16: error: redefinition of 'long long int z'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |                ^
a.cc:115:16: note: 'long long int z' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |                ^
a.cc:242:18: error: redefinition of 'long long int p'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |                  ^
a.cc:115:18: note: 'long long int p' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |                  ^
a.cc:242:20: error: redefinition of 'long long int q'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |                    ^
a.cc:115:20: note: 'long long int q' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |                    ^
a.cc:242:22: error: redefinition of 'long long int w'
  242 | ll t,n,x,y,h,k,z,p,q,w;
      |                      ^
a.cc:115:22: note: 'long long int w' previously declared here
  115 | ll t,n,x,y,h,k,z,p,q,w;
      |                      ^
a.cc:243:8: error: redefinition of 'std::string s'
  243 | string s;
      |        ^
a.cc:116:8: note: 'std::string s' previously declared here
  116 | string s;
      |        ^
a.cc:247:5: error: redefinition of 'int main()'
  247 | int main() {
      |     ^~~~
a.cc:120:5: note: 'int main()' previously defined here
  120 | int main() {
      |     ^~~~