Submission #234352

#	Time	Username	Problem	Language	Result	Execution time	Memory
234352		caoash	Portals (BOI14_portals)	C++14	70 / 100	1103 ms	195904 KiB

portals

#pragma GCC target ("sse4")

#include <bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef pair<int, pi> pii;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

#define fax(i, a) for (int i = 0; i < (a); i++)
#define f0x(i, a, b) for (int i = (a); i < (b); i++)
#define f0xd(i,a,b) for (int i = (b)-1; i >= (a); i--)
#define faxd(i,a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto& a : x)
#define memeset memset

#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound

#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rsz resize

template<class T> void ckmin(T &a, T b) { a = min(a, b); }
template<class T> void ckmax(T &a, T b) { a = max(a, b); }

template <class T, int ...Ns> struct BIT {
    T val = 0;
    void upd(T v) { val += v; }
    T query() { return val; }
};
 
template <class T, int N, int... Ns> struct BIT<T, N, Ns...> {
    BIT<T,Ns...> bit[N + 1];
    template<typename... Args> void upd(int pos, Args... args) {
        for (; pos <= N; pos += (pos&-pos)) bit[pos].upd(args...);
    }
    template<typename... Args> T sum(int r, Args... args) {
        T res = 0; for (; r; r -= (r&-r)) res += bit[r].query(args...); 
        return res;
    }
    template<typename... Args> T query(int l, int r, Args... args) {
        return sum(r,args...)-sum(l-1,args...);
    }
};

namespace input {
    template<class T> void re(complex<T>& x);
    template<class T1, class T2> void re(pair<T1,T2>& p);
    template<class T> void re(vector<T>& a);
    template<class T, size_t SZ> void re(array<T,SZ>& a);

    template<class T> void re(T& x) { cin >> x; }
    void re(double& x) { string t; re(t); x = stod(t); }
    void re(ld& x) { string t; re(t); x = stold(t); }
    template<class T, class... Ts> void re(T& t, Ts&... ts) { 
        re(t); re(ts...); 
    }

    template<class T> void re(complex<T>& x) { T a,b; re(a,b); x = cd(a,b); }
    template<class T1, class T2> void re(pair<T1,T2>& p) { re(p.f,p.s); }
    template<class T> void re(vector<T>& a) { fax(i,sz(a)) re(a[i]); }
    template<class T, size_t SZ> void re(array<T,SZ>& a) { fax(i,SZ) re(a[i]); }
}

using namespace input;

namespace output {
    void pr(int x) { cout << x; }
    void pr(long x) { cout << x; }
    void pr(ll x) { cout << x; }
    void pr(unsigned x) { cout << x; }
    void pr(unsigned long x) { cout << x; }
    void pr(unsigned long long x) { cout << x; }
    void pr(float x) { cout << x; }
    void pr(double x) { cout << x; }
    void pr(ld x) { cout << x; }
    void pr(char x) { cout << x; }
    void pr(const char* x) { cout << x; }
    void pr(const string& x) { cout << x; }
    void pr(bool x) { pr(x ? "true" : "false"); }
    
    template<class T1, class T2> void pr(const pair<T1,T2>& x);
    template<class T> void pr(const T& x);
    
    template<class T, class... Ts> void pr(const T& t, const Ts&... ts) { 
        pr(t); pr(ts...); 
    }
    template<class T1, class T2> void pr(const pair<T1,T2>& x) { 
        pr("{",x.f,", ",x.s,"}"); 
    }
    template<class T> void pr(const T& x) { 
        pr("{"); // const iterator needed for vector<bool>
        bool fst = 1; for (const auto& a: x) pr(!fst?", ":"",a), fst = 0; 
        pr("}");
    }
    
    void ps() { pr("\n"); } // print w/ spaces
    template<class T, class... Ts> void ps(const T& t, const Ts&... ts) { 
        pr(t); if (sizeof...(ts)) pr(" "); ps(ts...); 
    }
    
    void pc() { pr("]\n"); } // debug w/ commas
    template<class T, class... Ts> void pc(const T& t, const Ts&... ts) { 
        pr(t); if (sizeof...(ts)) pr(", "); pc(ts...); 
    }
    #define dbg(x...) pr("[",#x,"] = ["), pc(x);
}

using namespace output;

namespace io {
    void setIn(string s) { freopen(s.c_str(),"r",stdin); }
    void setOut(string s) { freopen(s.c_str(),"w",stdout); }
    void setIO(string s = "") {
        ios_base::sync_with_stdio(0); cin.tie(0); // fast I/O
        if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
    }
}

using namespace io;

mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());

const int MOD = 1000000007; // 998244353
const ll INF = 1e18;
const int MX = 1005;
const ld PI = 4*atan((ld)1);
bool in[MX][MX]; map<pi, vector<pii>> adj; int d[MX][MX]; int x[MX][MX][4]; ll dist[MX][MX]; bool used[MX][MX];
int main() {
   setIO(); 
   int N,M; re(N,M);   
   pi st,en;
   fax(i,N) {
      string s; re(s);
      fax(j,M){
         if(s[j] == 'S'){
            st = mp(i,j);
         }
         else if(s[j] == 'C'){
            en = mp(i,j);
         }
         in[i][j] = (s[j] == '#');
      }
   }
   fax(i,N){
      fax(j,M){
         if(i != 0 && !in[i-1][j]) adj[mp(i,j)].pb(mp(1,mp(i-1,j)));
         if(j != 0 && !in[i][j-1]) adj[mp(i,j)].pb(mp(1,mp(i,j-1)));
         if(i != N-1 && !in[i+1][j]) adj[mp(i,j)].pb(mp(1,mp(i+1,j)));
         if(j != M-1 && !in[i][j+1]) adj[mp(i,j)].pb(mp(1,mp(i,j+1)));
      }
   }
   fax(i,N) fax(j,M) d[i][j] = INT_MAX;
   queue<pi> q; set<pi> vis;
   fax(i,N){
      fax(j,M){
         if(in[i][j]){
            d[i][j] = 0; q.push(mp(i,j));
         }
      }
   }
   fax(i,N){
      fax(j,M){
         if(in[i][j]){
            x[i][j][0] = 0; x[i][j][1] = 0;
         }
         else{
            if(i != 0) {
               x[i][j][0] = x[i-1][j][0] + 1;
            }
            else{
               x[i][j][0] = 1;
            }
            if(j != 0) {
               x[i][j][1] = x[i][j-1][1] + 1;
            }
            else{
               x[i][j][1] = 1;
            }
         }
      }
   }
   faxd(i,N){
      faxd(j,M){
         if(in[i][j]){
            x[i][j][2] = 0; x[i][j][3] = 0;
         }
         else{
            if(i != N-1) {
               x[i][j][2] = x[i+1][j][2] + 1;
            }
            else{
               x[i][j][2] = 1;
            }
            if(j != M-1) {
               x[i][j][3] = x[i][j+1][3] + 1;
            }
            else{
               x[i][j][3] = 1;
            }
         }
      }
   }
   while(!q.empty()){
      pi curr = q.front(); q.pop();
      for(pii to : adj[curr]){
         if(vis.count(to.s)) continue;
         if(d[to.s.f][to.s.s] > d[curr.f][curr.s]+1){
            d[to.s.f][to.s.s] = d[curr.f][curr.s]+1;
            q.push(mp(to.s.f, to.s.s));
         }
      }
      vis.insert(curr);
   }
   fax(i,N){
      fax(j,M){
         ckmin(d[i][j],min({i+1,j+1,N-i,M-j}));
      }
   }
   fax(i,N){
      fax(j,M){
         int W = d[i][j];
         adj[mp(i,j)].pb(mp(W, mp(i-x[i][j][0]+1, j)));
         adj[mp(i,j)].pb(mp(W, mp(i, j-x[i][j][1]+1)));
         adj[mp(i,j)].pb(mp(W, mp(i+x[i][j][2]-1, j)));
         adj[mp(i,j)].pb(mp(W, mp(i, j+x[i][j][3]-1)));
      }
   }
   fax(i,N){
      fax(j,M){
         dist[i][j] = INF;
      }
   }
   dist[st.f][st.s] = 0;
   priority_queue<pii, vector<pii>, greater<pii>> pq;
   pq.push(mp(0,mp(st.f, st.s)));
   while(!pq.empty()){
      pii curr = pq.top(); pq.pop();
      for(pii to : adj[curr.s]){
         if(used[to.s.f][to.s.s]) continue;
         if(dist[to.s.f][to.s.s] > dist[curr.s.f][curr.s.s] + to.f){
            dist[to.s.f][to.s.s] = dist[curr.s.f][curr.s.s] + to.f;
            pq.push(mp(dist[to.s.f][to.s.s], mp(to.s.f, to.s.s)));
         }
      }
      used[curr.s.f][curr.s.s] = true;
   }
   pr((dist[en.f][en.s] == INF) ? -1 : dist[en.f][en.s]);
}

Compilation message (stderr)

portals.cpp: In function 'void io::setIn(std::__cxx11::string)':
portals.cpp:133:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     void setIn(string s) { freopen(s.c_str(),"r",stdin); }
                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
portals.cpp: In function 'void io::setOut(std::__cxx11::string)':
portals.cpp:134:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     void setOut(string s) { freopen(s.c_str(),"w",stdout); }
                             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 19 / 19
• Subtask 5: 0 / 30