Submission #6932921


Source Code Expand

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

typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> P;

#define fi first
#define se second
#define repl(i,a,b) for(ll i=(ll)(a);i<(ll)(b);i++)
#define rep(i,n) repl(i,0,n)
#define all(x) (x).begin(),(x).end()
#define dbg(x) cout<<#x"="<<x<<endl
#define mmax(x,y) (x>y?x:y)
#define mmin(x,y) (x<y?x:y)
#define maxch(x,y) x=mmax(x,y)
#define minch(x,y) x=mmin(x,y)
#define uni(x) x.erase(unique(all(x)),x.end())
#define exist(x,y) (find(all(x),y)!=x.end())
#define bcnt __builtin_popcountll

#define INF 1e16
#define mod 1000000007

struct UnionFind{
  vector<int> v;
  UnionFind(int n) : v(n, -1) {}
  void init(){ for(int i = 0;i < (int)v.size();i++)v[i]=-1; }
  int find(int x) { return v[x] < 0 ? x : v[x] = find(v[x]); }
  bool unite(int x, int y) {
    x = find(x); y = find(y);
    if (x == y) return false;
    if (-v[x] < -v[y]) swap(x, y);
    v[x] += v[y]; v[y] = x;
    return true;
  }
  bool root(int x) { return v[x] < 0; }
  bool same(int x, int y) { return find(x) == find(y); }
  int size(int x) { return -v[find(x)]; }
};


ll mod_pow(ll a,ll n){
  ll res=1;
  while(n>0){
    if(n&1)res=res*a%mod;
    a=a*a%mod;
    n>>=1;
  }
  return res;
}

ll h,w;
vector<string> s;

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

  cin>>h>>w;
  s.resize(h);
  rep(i,h)cin>>s[i];

  ll res=1;
  if(h%2==1){
    ll mid=h/2;
    bool isp=true;
    rep(j,w)if(s[mid][j]!=s[mid][w-1-j])isp=false;
    if(!isp){
      res*=2;
    }

    vector<string> ns;
    rep(i,h){
      if(i==mid)continue;
      ns.push_back(s[i]);
    }
    s=ns;
    h--;
  }

  if(w%2==1){
    ll mid=w/2;
    bool isp=true;
    rep(i,h)if(s[i][mid]!=s[h-1-i][mid])isp=false;
    if(!isp){
      res*=2;
    }

    vector<string> ns;
    rep(i,h){
      string tmp;
      rep(j,w){
        if(j==mid)continue;
        tmp+=s[i][j];
      }
      ns.push_back(tmp);
    }
    s=ns;
    w--;
  }

  UnionFind uf((h/2)+(w/2));
  rep(i,h/2)rep(j,w/2){
    map<char,ll> cnt;
    cnt[s[i][j]]++;
    cnt[s[i][w-1-j]]++;
    cnt[s[h-1-i][j]]++; 
    cnt[s[h-1-i][w-1-j]]++;

    if(cnt.size()==4){
      uf.unite(i,(h/2)+j);
      res*=mod_pow(2,mod-2);
      res%=mod;
    }

    ll cnta=24;
    for(auto it : cnt){
      cnta*=mod_pow(it.se,mod-2);
      cnta%=mod;
    }
    res*=cnta;
  }

  set<ll> comp;
  rep(i,h/2)comp.insert(uf.find(i));
  rep(j,w/2)comp.insert(uf.find((h/2)+j));

  res*=mod_pow(2,(h/2)+(w/2)-comp.size());
  res%=mod;
  cout<<res<<endl;

  return 0;
}

Submission Info

Submission Time
Task I - Reverse Grid
User yamad
Language C++14 (GCC 5.4.1)
Score 0
Code Size 2665 Byte
Status WA
Exec Time 11 ms
Memory 384 KB

Judge Result

Set Name sample all
Score / Max Score 0 / 0 0 / 1900
Status
AC × 2
AC × 12
WA × 27
Set Name Test Cases
sample sample-01.txt, sample-02.txt
all sample-01.txt, sample-02.txt, 01-01.txt, 01-02.txt, 01-03.txt, 01-04.txt, 01-05.txt, 01-06.txt, 01-07.txt, 01-08.txt, 01-09.txt, 01-10.txt, 01-11.txt, 01-12.txt, 01-13.txt, 01-14.txt, 01-15.txt, 01-16.txt, 01-17.txt, 01-18.txt, 01-19.txt, 01-20.txt, 01-21.txt, 01-22.txt, 01-23.txt, 01-24.txt, 01-25.txt, 01-26.txt, 01-27.txt, 01-28.txt, 01-29.txt, 01-30.txt, 01-31.txt, 01-32.txt, 01-33.txt, 01-34.txt, 01-35.txt, sample-01.txt, sample-02.txt
Case Name Status Exec Time Memory
01-01.txt AC 2 ms 256 KB
01-02.txt AC 2 ms 256 KB
01-03.txt AC 2 ms 256 KB
01-04.txt AC 2 ms 256 KB
01-05.txt WA 2 ms 256 KB
01-06.txt AC 2 ms 256 KB
01-07.txt AC 2 ms 256 KB
01-08.txt AC 2 ms 256 KB
01-09.txt AC 2 ms 256 KB
01-10.txt WA 4 ms 384 KB
01-11.txt WA 6 ms 384 KB
01-12.txt WA 6 ms 384 KB
01-13.txt WA 4 ms 384 KB
01-14.txt WA 3 ms 256 KB
01-15.txt WA 4 ms 256 KB
01-16.txt WA 11 ms 256 KB
01-17.txt WA 11 ms 384 KB
01-18.txt WA 11 ms 256 KB
01-19.txt WA 8 ms 384 KB
01-20.txt WA 8 ms 384 KB
01-21.txt WA 8 ms 256 KB
01-22.txt WA 2 ms 256 KB
01-23.txt WA 6 ms 384 KB
01-24.txt WA 9 ms 384 KB
01-25.txt WA 9 ms 256 KB
01-26.txt WA 9 ms 256 KB
01-27.txt WA 2 ms 256 KB
01-28.txt WA 3 ms 256 KB
01-29.txt WA 2 ms 256 KB
01-30.txt WA 3 ms 256 KB
01-31.txt WA 11 ms 384 KB
01-32.txt WA 11 ms 384 KB
01-33.txt WA 11 ms 384 KB
01-34.txt WA 11 ms 384 KB
01-35.txt WA 11 ms 256 KB
sample-01.txt AC 2 ms 256 KB
sample-02.txt AC 2 ms 256 KB