Submission #571015

#	Time	Username	Problem	Language	Result	Execution time	Memory
571015		f4t4nt	Mecho (IOI09_mecho)	C++11	84 / 100	354 ms	16428 KiB

mecho

#include <algorithm>
#include <cmath>
#include <ctime>
#include <deque>
#include <fstream>
#include <functional>
#include <iostream>
#include <iomanip>
#include <iterator>
#include <list>
#include <map>
#include <math.h>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <stdio.h>
#include <string>
#include <tuple>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using ll = long long;
using ull = unsigned long long;
using ld = long double;
using ch = char;
using str = string;

#define pb push_back
#define elif else if
#define sz(C) (ll) C.size()
#define mp make_pair
#define mt make_tuple
#define flip(C) reverse(C.begin(), C.end())
#define ssort(C) sort(C.begin(), C.end())
#define rsort(C) sort(C.begin(), C.end(), greater<>())

#define FOR(x, e) for(ll  x = 0; x < (ll) e; x++)
#define FORR(x, e) for(ll x = (ll) e - 1; x >= 0; x--)
#define FOB(x, b, e) for(auto x = b; x < e; x++)
#define FOI(x, e, i) for(ll x = 0; x < (ll) e; x += (ll) i)
#define FOBI(x, b, e, i) for(ll x = (ll) b; x < (ll) e; x += (ll) i)
#define FORE(x, C) for(auto &x : C)

#ifdef LOCAL
#include "tester.cpp"
#define main test_main
extern istringstream fin;
extern ostringstream fout;
string test_file_name = "tests";
#define cin fin
#define cout fout
#endif

vector<int> di { -1, 0, 1, 0};
vector<int> dj { 0, -1, 0, 1};

void fill_b(ll &n, vector<vector<char>> &g, queue<pair<ll, ll>> &bfs_b, vector<vector<ll>> &d_b) {
    while(sz(bfs_b)) {
        ll i0 = bfs_b.front().first, j0 = bfs_b.front().second;
        bfs_b.pop();
        FOR(k, 4) {
            ll i1 = i0 + di[k], j1 = j0 + dj[k];
            if(i1 < 0 || i1 >= n || j1 < 0 || j1 >= n) continue;
            if(g[i1][j1] == 'T' || g[i1][j1] == 'D') continue;
            if(d_b[i1][j1] != 1e18) continue;
            d_b[i1][j1] = d_b[i0][j0] + 1;
            bfs_b.push({i1, j1});
        }
    }
}

bool valid(ll &mid, ll &n, ll &s, vector<vector<ll>> &d_b, vector<vector<char>> &g, queue<pair<ll, ll>> bfs_m, vector<vector<ll>> d_m) {
    while(sz(bfs_m)) {
        ll i0 = bfs_m.front().first, j0 = bfs_m.front().second, d = d_m[i0][j0] + 1;
        bfs_m.pop();
        FOR(k, 4) {
            ll i1 = i0 + di[k], j1 = j0 + dj[k];
            if(i1 < 0 || i1 >= n || j1 < 0 || j1 >= n) continue;
            if(g[i1][j1] == 'T') continue;
            if(d_m[i1][j1] != 1e18) continue;
            if(d_b[i1][j1] < mid + d / s) continue;
            if(g[i1][j1] == 'D') return true;
            d_m[i1][j1] = d;
            bfs_m.push({i1, j1});
        }
    }
    return false;
}

int main() {
    ll n, s, lo = 0, hi = 1e18;
    cin >> n >> s;
    vector<vector<char>> g(n, vector<char>(n));
    vector<vector<ll>> d_b(n, vector<ll>(n, 1e18)), d_m(n, vector<ll>(n, 1e18));
    queue<pair<ll, ll>> bfs_b, bfs_m;
    FOR(i, n) FOR(j, n) {
        cin >> g[i][j];
        if(g[i][j] == 'H') {
            bfs_b.push({i, j});
            d_b[i][j] = 0;
        }
        elif(g[i][j] == 'M') {
            bfs_m.push({i, j});
            d_m[i][j] = 0;
        }
    }
    fill_b(n, g, bfs_b, d_b);
    while(hi - lo > 0) {
        ll mid = lo + (hi - lo + 1) / 2;
        if(valid(mid, n, s, d_b, g, bfs_m, d_m)) lo = mid;
        else hi = mid - 1;
    }
    cout << lo - 1 << '\n';
    return 0;
}

• Subtask 1: 84 / 100