Submission #1326089

#	Time	Username	Problem	Language	Result	Execution time	Memory
1326089		hectormedrano	Mecho (IOI09_mecho)	C++20	11 / 100	1097 ms	47516 KiB

mecho

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

vector<vector<ll>> v;
ll N, S, ini, fin;

bool solve(ll T, deque<pair<ll, ll>> bfs, vector<bool> vis, vector<char> ori){
    bfs.push_front({ini, -(T+1)});
    vis[ini] = true;
    while(bfs.size() != 0){
        pair<ll, ll> p = bfs.front();
        ll x = p.first;
        ll e = p.second;
        bfs.pop_front();
        if(e == -1){
            bfs.push_front({x, S+1});
            continue;
        }
        if(e < -1){
            bfs.push_back({x, e+1});
            continue;
        }
        for(ll y : v[x]){
            if(vis[y]){continue;}
            if(ori[y] == 'D' and ori[x] == 'H'){continue;}
            vis[y] = true;
            ori[y] = ori[x];
            //cout<<"Casilla "<<y/N<<" "<<y%N<<" pasa a tener origen "<<ori[y]<<endl;
            if(e == 1){bfs.push_back({y, S+1});}
            if(e > 1){bfs.push_front({y, e-1});}
            if(e == 0){bfs.push_back({y, 0});}
        }
    }

    return (ori[fin] == 'M');
}

int main() {
	cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    cin>>N>>S;
    v.resize(N*N);
    vector<char> c(N*N);
    deque<pair<ll, ll>> d;
    vector<bool> fij(N*N, false);
    for(ll i=0;i<N;i++){
        for(ll j=0;j<N;j++){
            cin>>c[N*i+j];
            if(c[N*i+j] == 'H'){
                d.push_back({N*i+j, 0});
                fij[N*i+j] = true;
            }
            if(c[N*i+j] == 'M'){ini = N*i+j;}
            if(c[N*i+j] == 'D'){
                fin = N*i+j;
            }
        }
    }
    for(ll i=0;i<N;i++){
        for(ll j=0;j<N;j++){
            if(i > 0 and c[N*(i-1)+j] != 'T'){
                v[N*i+j].push_back(N*(i-1)+j);
            }
            if(i < N-1 and c[N*(i+1)+j] != 'T'){
                v[N*i+j].push_back(N*(i+1)+j);
            }
            if(j > 0 and c[N*i+(j-1)] != 'T'){
                v[N*i+j].push_back(N*i+(j-1));
            }
            if(j < N-1 and c[N*i+(j+1)] != 'T'){
                v[N*i+j].push_back(N*i+(j+1));
            }
        }
    }
    solve(1, d, fij, c);
    if(!(solve(0, d, fij, c))){cout<<-1; return 0;}
    ll l = 0;
    ll r = N*N;
    while(r != l+1){
        ll m = (l+r)/2;
        if(solve(m, d, fij, c)){l = m;}
        else{r = m;}
        //cout<<l<<" "<<r<<endl;
    }
    cout<<l;
}

• Subtask 1: 11 / 100