Submission #953274

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
953274	2024-03-25T19:00:05 Z	dpsaveslives	Mecho (IOI09_mecho)	C++17	100 / 100	165 ms	16472 KB

mecho

#include <bits/stdc++.h>
#define int long long
#define f first
#define s second
using namespace std;
const int MAXN = 810;
char grid[MAXN][MAXN];
int dr[4] = {0,0,1,-1}, dc[4] = {1,-1,0,0},N;
bool goodbees(int r, int c){
    return r >= 0 && c >= 0 && r <= N-1 && c <= N-1 && grid[r][c] != 'T' && grid[r][c] != 'D';
}
bool goodmecho(int r, int c){
    return r >= 0 && c >= 0 && r <= N-1 && c <= N-1 && grid[r][c] != 'T';
}
const int INF = 1e18;
int32_t main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int S; cin >> N >> S;
    queue<pair<int,int>> q;
    vector<vector<int>> dist(N,vector<int>(N,INF));
    pair<int,int> m,home;
    for(int i = 0;i<N;++i){
        for(int j = 0;j<N;++j){
            cin >> grid[i][j];
            if(grid[i][j] == 'H'){
                q.push({i,j});
                dist[i][j] = 0;
            }
            else if(grid[i][j] == 'M'){
                m.f = i, m.s = j;
            }
            else if(grid[i][j] == 'D'){
                home.f = i, home.s = j;
            }
        }
    }
    while(!q.empty()){
        int r = q.front().f, c = q.front().s; q.pop();
        for(int i = 0;i<4;++i){
            int nr = r+dr[i], nc = c+dc[i];
            if(goodbees(nr,nc)){
                if(dist[nr][nc] > dist[r][c]+1){
                    dist[nr][nc] = dist[r][c]+1;
                    q.push({nr,nc});
                }
            }
        }
    }
    /*vector<vector<int>> mecho(N,vector<int>(N,INF));
    mecho[m.f][m.s] = 0; q.push(m);
    while(!q.empty()){
        int r = q.front().f, c = q.front().s; q.pop();
        for(int i = 0;i<4;++i){
            int nr = r+dr[i], nc = c+dc[i];
            if(goodmecho(nr,nc)){
                if(mecho[nr][nc] > mecho[r][c]+1){
                    mecho[nr][nc] = mecho[r][c]+1;
                    q.push({nr,nc});
                }
            }
        }
    }*/
    int lo = 0, hi = dist[m.f][m.s]-1;
    vector<vector<int>> D(N,vector<int>(N,INF));
    --lo;
    while(lo < hi){
        int mid = lo+(hi-lo+1)/2; //time
        //cout << mid << "\n";
        D = vector<vector<int>>(N,vector<int>(N,INF));
        q.push(m); D[m.f][m.s] = 0;
        while(!q.empty()){
            int r = q.front().f, c = q.front().s; q.pop();
            //cout << r << " " << c << "\n";
            for(int i = 0;i<4;++i){
                int nr = r+dr[i], nc = c+dc[i];
                if(goodmecho(nr,nc)){
                    if((D[r][c]+1)/S +mid < dist[nr][nc] && D[r][c]+1 < D[nr][nc]){
                        D[nr][nc] = D[r][c]+1;
                        q.push({nr,nc});
                    }
                }
            }
        }
        if(D[home.f][home.s] == INF){
            hi = mid-1;
        }
        else{
            lo = mid;
        }
    }
    cout << lo << "\n";
    return 0;
}

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	348 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	348 KB	Output is correct
4	Correct	0 ms	348 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	96 ms	16220 KB	Output is correct
8	Correct	0 ms	348 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	0 ms	348 KB	Output is correct
11	Correct	1 ms	348 KB	Output is correct
12	Correct	1 ms	856 KB	Output is correct
13	Correct	0 ms	348 KB	Output is correct
14	Correct	1 ms	600 KB	Output is correct
15	Correct	0 ms	348 KB	Output is correct
16	Correct	0 ms	348 KB	Output is correct
17	Correct	0 ms	348 KB	Output is correct
18	Correct	0 ms	348 KB	Output is correct
19	Correct	0 ms	344 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct
21	Correct	0 ms	348 KB	Output is correct
22	Correct	1 ms	348 KB	Output is correct
23	Correct	0 ms	348 KB	Output is correct
24	Correct	0 ms	348 KB	Output is correct
25	Correct	0 ms	604 KB	Output is correct
26	Correct	0 ms	348 KB	Output is correct
27	Correct	1 ms	604 KB	Output is correct
28	Correct	1 ms	604 KB	Output is correct
29	Correct	1 ms	604 KB	Output is correct
30	Correct	1 ms	604 KB	Output is correct
31	Correct	1 ms	604 KB	Output is correct
32	Correct	1 ms	604 KB	Output is correct
33	Correct	6 ms	3656 KB	Output is correct
34	Correct	7 ms	3652 KB	Output is correct
35	Correct	17 ms	3600 KB	Output is correct
36	Correct	8 ms	4588 KB	Output is correct
37	Correct	8 ms	4836 KB	Output is correct
38	Correct	25 ms	4588 KB	Output is correct
39	Correct	10 ms	5660 KB	Output is correct
40	Correct	11 ms	5656 KB	Output is correct
41	Correct	32 ms	5604 KB	Output is correct
42	Correct	13 ms	6800 KB	Output is correct
43	Correct	14 ms	7028 KB	Output is correct
44	Correct	40 ms	6744 KB	Output is correct
45	Correct	15 ms	8104 KB	Output is correct
46	Correct	16 ms	8076 KB	Output is correct
47	Correct	51 ms	7944 KB	Output is correct
48	Correct	18 ms	9444 KB	Output is correct
49	Correct	20 ms	9484 KB	Output is correct
50	Correct	59 ms	9400 KB	Output is correct
51	Correct	22 ms	11000 KB	Output is correct
52	Correct	23 ms	11000 KB	Output is correct
53	Correct	69 ms	10904 KB	Output is correct
54	Correct	25 ms	12604 KB	Output is correct
55	Correct	26 ms	12652 KB	Output is correct
56	Correct	83 ms	12576 KB	Output is correct
57	Correct	29 ms	14356 KB	Output is correct
58	Correct	31 ms	14396 KB	Output is correct
59	Correct	123 ms	14356 KB	Output is correct
60	Correct	33 ms	16224 KB	Output is correct
61	Correct	35 ms	16264 KB	Output is correct
62	Correct	132 ms	16220 KB	Output is correct
63	Correct	97 ms	16228 KB	Output is correct
64	Correct	165 ms	16428 KB	Output is correct
65	Correct	153 ms	16172 KB	Output is correct
66	Correct	111 ms	16224 KB	Output is correct
67	Correct	103 ms	16176 KB	Output is correct
68	Correct	47 ms	16172 KB	Output is correct
69	Correct	43 ms	16208 KB	Output is correct
70	Correct	40 ms	16208 KB	Output is correct
71	Correct	35 ms	16220 KB	Output is correct
72	Correct	35 ms	16212 KB	Output is correct
73	Correct	39 ms	16216 KB	Output is correct
74	Correct	65 ms	16156 KB	Output is correct
75	Correct	80 ms	16208 KB	Output is correct
76	Correct	73 ms	16212 KB	Output is correct
77	Correct	73 ms	16264 KB	Output is correct
78	Correct	78 ms	16220 KB	Output is correct
79	Correct	74 ms	16212 KB	Output is correct
80	Correct	68 ms	16276 KB	Output is correct
81	Correct	68 ms	16172 KB	Output is correct
82	Correct	66 ms	16240 KB	Output is correct
83	Correct	89 ms	16220 KB	Output is correct
84	Correct	70 ms	16216 KB	Output is correct
85	Correct	69 ms	16172 KB	Output is correct
86	Correct	93 ms	16208 KB	Output is correct
87	Correct	74 ms	16220 KB	Output is correct
88	Correct	90 ms	16208 KB	Output is correct
89	Correct	84 ms	16472 KB	Output is correct
90	Correct	91 ms	16268 KB	Output is correct
91	Correct	89 ms	16212 KB	Output is correct
92	Correct	90 ms	16236 KB	Output is correct