답안 #587486

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
587486	2022-07-02T01:14:08 Z	Agnimandur	Mecho (IOI09_mecho)	C++17	100 / 100	359 ms	6356 KB

mecho

#include <bits/stdc++.h>
 
#define ll long long
#define sz(x) ((int) (x).size())
#define all(x) (x).begin(), (x).end()
#define vi vector<int>
#define si set<int>
#define vvi vector<vector<int>>
#define vvl vector<vector<long long>>
#define vl vector<long long>
#define pii pair<int, int>
#define pll pair<ll,ll>
#define add push_back
#define REP(i,a) for (int i = 0; i < (a); i++)
using namespace std;
 
template<typename T>
using minpq = priority_queue<T, vector<T>, greater<T>>;
const int INF = 1005000000; 
//const ll MOD = 1000000007LL;
const ll MOD = 998244353LL;
 
int ni() {
    int x; cin >> x;
    return x;
}
 
ll nl() {
    ll x; cin >> x;
    return x;
}
 
double nd() {
    double x; cin >> x;
    return x;
}

string next() {
    string x; cin >> x;
    return x;
}

int N,S;
char grid[800][800];
pii mecho1;
pii mecho2;
vector<pii> hives;
vvi dirs = {{-1,0},{1,0},{0,-1},{0,1}};

void printDist(vvi dist) {
    REP(i,N) REP(j,N) {
        if (dist[i][j]==INF)
            cout << "I";
        else
            cout << dist[i][j];
        if (j==N-1) cout << '\n';
    }
}

bool solve(int headstart) {
    vvi mechoDist(N,vi(N,INF));
    queue<pii> mechoQ;
    mechoDist[mecho1.first][mecho1.second] = 0;
    mechoQ.push(mecho1);

    vvi beeDist(N,vi(N,INF));
    queue<pii> beeQ;
    for (pii& hive: hives) {
        beeDist[hive.first][hive.second] = 0;
        beeQ.push(hive);
    }
    while (!beeQ.empty()) {
        pii p = beeQ.front();
        if (beeDist[p.first][p.second] == headstart) break;
        beeQ.pop();
        for (vi& dir: dirs) {
            int newR = p.first+dir[0];
            int newC = p.second+dir[1];
            if (newR >= 0 && newR < N && newC >= 0 && newC < N && beeDist[newR][newC]==INF && grid[newR][newC] != 'T' && grid[newR][newC] != 'D') {
                beeDist[newR][newC] = beeDist[p.first][p.second]+1;
                beeQ.push({newR,newC});
            }
        }
    }

    int travel = 0;
    while (!mechoQ.empty()) {
        travel += S;
        //mecho moves up to travel spaces from the origin.
        while (!mechoQ.empty()) {
            pii p = mechoQ.front();
            if (mechoDist[p.first][p.second] == travel) break;
            mechoQ.pop();
            if (beeDist[p.first][p.second] < INF) {
                //bees control this cell already
                continue;
            }
            for (vi& dir: dirs) {
                int newR = p.first+dir[0];
                int newC = p.second+dir[1];
                if (newR >= 0 && newR < N && newC >= 0 && newC < N && mechoDist[newR][newC]==INF && grid[newR][newC] != 'T' && grid[newR][newC] != 'H' && beeDist[newR][newC] == INF) {
                    mechoDist[newR][newC] = mechoDist[p.first][p.second]+1;
                    mechoQ.push({newR,newC});
                }
            }
        }

        headstart++;
        while (!beeQ.empty()) {
            pii p = beeQ.front();
            if (beeDist[p.first][p.second] == headstart) break;
            beeQ.pop();
            for (vi& dir: dirs) {
                int newR = p.first+dir[0];
                int newC = p.second+dir[1];
                if (newR >= 0 && newR < N && newC >= 0 && newC < N && beeDist[newR][newC]==INF && grid[newR][newC] != 'T' && grid[newR][newC] != 'D') {
                    beeDist[newR][newC] = beeDist[p.first][p.second]+1;
                    beeQ.push({newR,newC});
                }
            }
        }
    }

    if (mechoDist[mecho2.first][mecho2.second] < INF) {
        //he can reach his home!
        return true;
    } else {
        return false;
    }
}

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

    N = ni();
    S = ni();
    REP(i,N) {
        string s = next();
        REP(j,N) {
            grid[i][j] = s[j];
            if (grid[i][j]=='M')
                mecho1 = {i,j};
            else if (grid[i][j]=='D')
                mecho2 = {i,j};
            else if (grid[i][j]=='H')
                hives.add({i,j});
        }
    }

    int lo = 0;
    int hi = N*N;
    if (!solve(0)) {
        //mecho can't reach the house ever
        cout << -1;
        return 0;
    }
    while (lo < hi) {
        int m = (lo+hi+1)/2;
        if (solve(m)) {
            lo = m;
        } else {
            hi = m-1;
        }
    }
    cout << lo;
}

Subtask #1

100.0 / 100.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	0 ms	212 KB	Output is correct
4	Correct	0 ms	212 KB	Output is correct
5	Correct	0 ms	212 KB	Output is correct
6	Correct	1 ms	232 KB	Output is correct
7	Correct	304 ms	6160 KB	Output is correct
8	Correct	0 ms	340 KB	Output is correct
9	Correct	0 ms	340 KB	Output is correct
10	Correct	0 ms	212 KB	Output is correct
11	Correct	1 ms	212 KB	Output is correct
12	Correct	1 ms	340 KB	Output is correct
13	Correct	1 ms	340 KB	Output is correct
14	Correct	1 ms	340 KB	Output is correct
15	Correct	0 ms	340 KB	Output is correct
16	Correct	1 ms	340 KB	Output is correct
17	Correct	0 ms	340 KB	Output is correct
18	Correct	0 ms	340 KB	Output is correct
19	Correct	0 ms	340 KB	Output is correct
20	Correct	1 ms	340 KB	Output is correct
21	Correct	1 ms	340 KB	Output is correct
22	Correct	1 ms	340 KB	Output is correct
23	Correct	1 ms	340 KB	Output is correct
24	Correct	1 ms	340 KB	Output is correct
25	Correct	1 ms	340 KB	Output is correct
26	Correct	1 ms	340 KB	Output is correct
27	Correct	1 ms	340 KB	Output is correct
28	Correct	1 ms	340 KB	Output is correct
29	Correct	2 ms	340 KB	Output is correct
30	Correct	1 ms	340 KB	Output is correct
31	Correct	1 ms	340 KB	Output is correct
32	Correct	1 ms	340 KB	Output is correct
33	Correct	30 ms	1580 KB	Output is correct
34	Correct	28 ms	1584 KB	Output is correct
35	Correct	37 ms	1592 KB	Output is correct
36	Correct	39 ms	1920 KB	Output is correct
37	Correct	41 ms	1952 KB	Output is correct
38	Correct	47 ms	1940 KB	Output is correct
39	Correct	52 ms	2332 KB	Output is correct
40	Correct	50 ms	2324 KB	Output is correct
41	Correct	65 ms	2300 KB	Output is correct
42	Correct	69 ms	2796 KB	Output is correct
43	Correct	58 ms	2712 KB	Output is correct
44	Correct	79 ms	2844 KB	Output is correct
45	Correct	83 ms	3180 KB	Output is correct
46	Correct	73 ms	3204 KB	Output is correct
47	Correct	96 ms	3212 KB	Output is correct
48	Correct	98 ms	3820 KB	Output is correct
49	Correct	93 ms	3704 KB	Output is correct
50	Correct	113 ms	3668 KB	Output is correct
51	Correct	120 ms	4324 KB	Output is correct
52	Correct	114 ms	4228 KB	Output is correct
53	Correct	139 ms	4204 KB	Output is correct
54	Correct	140 ms	4808 KB	Output is correct
55	Correct	130 ms	4796 KB	Output is correct
56	Correct	180 ms	4804 KB	Output is correct
57	Correct	158 ms	5416 KB	Output is correct
58	Correct	151 ms	5408 KB	Output is correct
59	Correct	193 ms	5404 KB	Output is correct
60	Correct	184 ms	6040 KB	Output is correct
61	Correct	182 ms	6068 KB	Output is correct
62	Correct	227 ms	6060 KB	Output is correct
63	Correct	332 ms	6176 KB	Output is correct
64	Correct	354 ms	6044 KB	Output is correct
65	Correct	303 ms	6040 KB	Output is correct
66	Correct	350 ms	6052 KB	Output is correct
67	Correct	18 ms	5972 KB	Output is correct
68	Correct	344 ms	6064 KB	Output is correct
69	Correct	284 ms	6092 KB	Output is correct
70	Correct	349 ms	6060 KB	Output is correct
71	Correct	357 ms	6064 KB	Output is correct
72	Correct	359 ms	6056 KB	Output is correct
73	Correct	255 ms	6344 KB	Output is correct
74	Correct	306 ms	6332 KB	Output is correct
75	Correct	325 ms	6352 KB	Output is correct
76	Correct	337 ms	6348 KB	Output is correct
77	Correct	332 ms	6356 KB	Output is correct
78	Correct	19 ms	6228 KB	Output is correct
79	Correct	316 ms	6324 KB	Output is correct
80	Correct	318 ms	6228 KB	Output is correct
81	Correct	334 ms	6296 KB	Output is correct
82	Correct	338 ms	6292 KB	Output is correct
83	Correct	327 ms	6244 KB	Output is correct
84	Correct	343 ms	6252 KB	Output is correct
85	Correct	343 ms	6248 KB	Output is correct
86	Correct	339 ms	6228 KB	Output is correct
87	Correct	320 ms	6248 KB	Output is correct
88	Correct	314 ms	6212 KB	Output is correct
89	Correct	347 ms	6300 KB	Output is correct
90	Correct	332 ms	6328 KB	Output is correct
91	Correct	315 ms	6200 KB	Output is correct
92	Correct	312 ms	6328 KB	Output is correct