Submission #3419702

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
// define
#define int long long
#define UNIQUE(v) v.erase(unique(all(v)), v.end());
#define ZIP(v) sort(all(v)),UNIQUE(v)
#define ADD(a, b) a = (a + b) % mod
#define SUB(a, b) a = (a+mod-b)%mod
#define MUL(a, b) a = (a * b) % mod
#define rollcall cout << "I'm Sucu." << endl;
#define repi(i,m,n) for(int i = m;i < n;i++)
#define drep(i,n,m) for(int i = n;i >= m;i--)
#define rep(i,n) repi(i,0,n)
#define rrep(i,n) repi(i,1,n+1)
#define chmin(x,y) x = min(x,y)
#define chmax(x,y) x = max(x,y)
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(), v.rend()
#define dmp(x,y) make_pair(x,y)
#define pb(x) push_back(x)
#define pf(x) push_front(x)
#define fi first
#define se second
// debug
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p){
  os << "(" << p.first << "," << p.second << ")";return os;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v){
  for (auto it = v.begin();it != v.end();++it){
    if(it != v.begin())os << " ";os << *it;
      }return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const map<T, U> &mp){
  for(auto x: mp)os << "(" << x.first << "," << x.second << ")" << endl;
  return os;
}
template<typename T, int SIZE>
int array_length(const T (&)[SIZE]){return SIZE;}
template<typename T, int N>
void PRINTF(const T (&a)[N], int s = N, int t = -1, bool f = true){
	if(t == -1){rep(i,s){if(i)cout << " ";cout << a[i];}}
	else repi(i,s,t){if(i!=s)cout << " ";cout << a[i];}
	if(f)cout << "\n";
}
template<typename T, int N1, int N2>
void PRINTF(const T (&a)[N1][N2], int h = N1, int w = N2){
	rep(i,h){rep(j,w){cout << a[i][j] << " \n"[j==w-1];}}
}
// typedef
typedef complex<double> Point;
// typedef pair<int, int> P;
// typedef pair<int, P> PP;
// typedef pair<P, int> Pi;
typedef vector<int> vi;
typedef deque<int> dq;
const int inf = 1e9+7;
const int INF = 1e18+7;
const int MAX = 3e3;

typedef pair<string, string> P;
string str;
map<P, int> mp;
signed main(){
  int n;
  cin >> n >> str;
  rep(s,1<<n){
    string s1 = "", s2 = "";
    rep(j,n){
      if(s & (1<<j))s1.pb(str[n+j]);
      else s2.pb(str[n+j]);
    }
    reverse(all(s1));
    reverse(all(s2));
    mp[P(s2, s1)]++;
  }
  int ans = 0;
  rep(s,1<<n){
    string s1 = "", s2 = "";
    rep(j,n){
      if(s & (1<<j))s1.pb(str[j]);
      else s2.pb(str[j]);
    }
    ans += mp[P(s1, s2)];
  }
  printf("%lld\n", ans);
  return 0;
}

Submission Info

Judge Result