제출 #988359

#제출 시각아이디문제언어결과실행 시간메모리
988359steveonalexMecho (IOI09_mecho)C++17
67 / 100
215 ms8016 KiB
#include <bits/stdc++.h> using namespace std; typedef long long ll; typedef unsigned long long ull; #define MASK(i) (1ULL << (i)) #define GETBIT(mask, i) (((mask) >> (i)) & 1) #define ALL(v) (v).begin(), (v).end() ll max(ll a, ll b){return (a > b) ? a : b;} ll min(ll a, ll b){return (a < b) ? a : b;} ll LASTBIT(ll mask){return (mask) & (-mask);} int pop_cnt(ll mask){return __builtin_popcountll(mask);} int ctz(ull mask){return __builtin_ctzll(mask);} int logOf(ull mask){return 63 - __builtin_clzll(mask);} mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count()); ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);} template <class T1, class T2> bool maximize(T1 &a, T2 b){ if (a < b) {a = b; return true;} return false; } template <class T1, class T2> bool minimize(T1 &a, T2 b){ if (a > b) {a = b; return true;} return false; } template <class T> void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){ for(auto item: container) out << item << separator; out << finish; } template <class T> void remove_dup(vector<T> &a){ sort(ALL(a)); a.resize(unique(ALL(a)) - a.begin()); } int dx[] = {0, 0, 1, -1}; int dy[] = {1, -1, 0, 0}; const int N = 900; const int INF = 1e6 + 69; int n, s; bitset<N> grid[N]; int dis1[N][N], dis2[N][N]; int main(void){ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n >> s; vector<string> field(n); for(int i = 0; i<n; ++i) cin >> field[i]; for(int i = 0; i<=n+1; ++i) grid[i][0] = grid[0][i] = grid[i][n+1] = grid[n+1][i] = 1; for(int i = 0; i<n; ++i) for(int j = 0 ;j<n; ++j) if (field[i][j] == 'T' || field[i][j] == 'D'){ grid[i+1][j+1] = 1; } for(int i = 0; i<=n+1; ++i) for(int j = 0; j<=n+1; ++j) dis1[i][j] = INF; deque<pair<int, int>> q; for(int i = 0; i<n; ++i) for(int j = 0; j<n; ++j) if (field[i][j] == 'H') { q.push_back({i + 1, j+1}); dis1[i+1][j+1] = 0; } while(q.size()){ pair<int, int> u = q.front(); q.pop_front(); for(int dir = 0; dir < 4; ++dir){ pair<int, int> v = {u.first + dx[dir], u.second + dy[dir]}; if (!grid[v.first][v.second] && minimize(dis1[v.first][v.second], dis1[u.first][u.second] + 1)){ q.push_back(v); } } } pair<int, int> S, E; for(int i = 0; i<n; ++i) for(int j = 0; j<n; ++j){ if (field[i][j] == 'D') E = {i+1, j+1}; if (field[i][j] == 'M') S = {i+1, j+1}; } grid[E.first][E.second] = 0; ll l = -1, r = 2 * n * n; minimize(r, dis1[S.first][S.second] * s - 1); while(l < r){ ll mid = (l + r + 1) >> 1; for(int i = 0; i<=n+1; ++i) for(int j = 0; j<=n+1; ++j) dis2[i][j] = INF; dis2[S.first][S.second] = mid; deque<pair<int, int>> q; q.push_back(S); while(q.size()){ pair<int, int> u = q.front(); q.pop_front(); int cur = dis2[u.first][u.second]; for(int dir = 0; dir < 4; ++dir){ pair<int, int> v = {u.first + dx[dir], u.second + dy[dir]}; if (!grid[v.first][v.second] && dis1[v.first][v.second] > (cur + 1) / s && minimize(dis2[v.first][v.second], cur + 1)){ q.push_back(v); } } } if (dis2[E.first][E.second] == INF) r = mid - 1; else l = mid; } if (l == n * n * 2) exit(1); if (l >= 0) l /= s; cout << l << "\n"; return 0; }
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