Submission #535603

# Submission time Handle Problem Language Result Execution time Memory
535603 2022-03-10T16:26:44 Z louiskwok Mecho (IOI09_mecho) C++17
45 / 100
200 ms 17860 KB
#include <bits/stdc++.h>
using namespace std;
bool visited[805][805];
int distBee[805][805];
double distBear[805][805];
char g[805][805];
int dr[] = {-1,0,1,0};
int dc[] = {0,1,0,-1};
int n,sr,sc,er,ec,mxtime;
double s;
bool success;
bool possible(double t) {
    memset(visited,0,sizeof visited);
    queue < pair<int,int> > bfs;
    distBear[sr][sc] = t;
    bfs.push({sr,sc});
    while (!bfs.empty()) {
        int curR = bfs.front().first;
        int curC = bfs.front().second;
        bfs.pop();
        for (int i=0;i<4;i++) {
            int nr = curR + dr[i];
            int nc = curC + dc[i];
            if (nr<1||nr>n||nc<1||nc>n||visited[nr][nc]||g[nr][nc]=='T'||distBear[curR][curC]+(double)1/s>=(double)distBee[nr][nc]) continue;
            visited[nr][nc] = true;
            distBear[nr][nc] = distBear[curR][curC]+1/s;
            bfs.push({nr,nc});
        }
    }
    if (visited[er][ec]) {
        success = true;
        return true;
    }
    return false;
}
int main() {
    queue < pair<int,int> > bfs;
    cin >> n >> s;
    for (int i=1;i<=n;i++) {
        for (int j=1;j<=n;j++) {
            cin >> g[i][j];
            if (g[i][j]=='M') sr = i,sc = j;
            else if (g[i][j]=='D') er = i,ec = j;
            else if (g[i][j]=='H') {
                visited[i][j] = true;
                bfs.push({i,j});
            }
        }
    }
    while (!bfs.empty()) {
        int curR = bfs.front().first;
        int curC = bfs.front().second;
        bfs.pop();
        for (int i=0;i<4;i++) {
            int nr = curR + dr[i];
            int nc = curC + dc[i];
            if (nr<1||nr>n||nc<1||nc>n||visited[nr][nc]||g[nr][nc]=='T') continue;
            visited[nr][nc] = true;
            distBee[nr][nc] = distBee[curR][curC]+1;
            mxtime = max(mxtime,distBee[nr][nc]);
            bfs.push({nr,nc});
        }
    }
    int cnt = 0;
    int lo = 0,hi = mxtime;
    while (lo<hi) {
        int mid = (lo+hi+1)/2;
        if (possible((double)mid)) lo = mid;
        else hi = mid-1;
    }
    if (success) cout << lo << endl;
    else cout << -1/0 << endl;
    return 0;
}

Compilation message

mecho.cpp: In function 'int main()':
mecho.cpp:72:20: warning: division by zero [-Wdiv-by-zero]
   72 |     else cout << -1/0 << endl;
      |                  ~~^~
mecho.cpp:64:9: warning: unused variable 'cnt' [-Wunused-variable]
   64 |     int cnt = 0;
      |         ^~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 980 KB Output is correct
2 Runtime error 2 ms 1748 KB Execution killed with signal 8
3 Correct 1 ms 852 KB Output is correct
4 Runtime error 2 ms 1748 KB Execution killed with signal 8
5 Runtime error 2 ms 1748 KB Execution killed with signal 8
6 Runtime error 2 ms 1876 KB Execution killed with signal 8
7 Incorrect 142 ms 7356 KB Output isn't correct
8 Runtime error 2 ms 1748 KB Execution killed with signal 8
9 Correct 1 ms 980 KB Output is correct
10 Correct 1 ms 980 KB Output is correct
11 Correct 1 ms 980 KB Output is correct
12 Runtime error 3 ms 2644 KB Execution killed with signal 8
13 Incorrect 2 ms 1236 KB Output isn't correct
14 Runtime error 3 ms 2388 KB Execution killed with signal 8
15 Correct 1 ms 980 KB Output is correct
16 Correct 1 ms 980 KB Output is correct
17 Correct 1 ms 980 KB Output is correct
18 Correct 1 ms 980 KB Output is correct
19 Correct 1 ms 980 KB Output is correct
20 Correct 1 ms 1108 KB Output is correct
21 Correct 1 ms 1108 KB Output is correct
22 Correct 1 ms 1108 KB Output is correct
23 Correct 1 ms 1108 KB Output is correct
24 Correct 1 ms 1236 KB Output is correct
25 Correct 2 ms 1236 KB Output is correct
26 Correct 1 ms 1236 KB Output is correct
27 Correct 1 ms 1236 KB Output is correct
28 Correct 1 ms 1236 KB Output is correct
29 Correct 1 ms 1236 KB Output is correct
30 Correct 2 ms 1364 KB Output is correct
31 Correct 1 ms 1236 KB Output is correct
32 Correct 2 ms 1364 KB Output is correct
33 Correct 11 ms 2772 KB Output is correct
34 Correct 12 ms 3300 KB Output is correct
35 Correct 33 ms 4516 KB Output is correct
36 Correct 15 ms 3028 KB Output is correct
37 Correct 16 ms 3640 KB Output is correct
38 Correct 34 ms 5020 KB Output is correct
39 Correct 17 ms 3284 KB Output is correct
40 Correct 19 ms 4072 KB Output is correct
41 Correct 48 ms 5464 KB Output is correct
42 Correct 19 ms 3476 KB Output is correct
43 Correct 22 ms 4428 KB Output is correct
44 Correct 64 ms 6156 KB Output is correct
45 Correct 28 ms 3808 KB Output is correct
46 Correct 26 ms 4768 KB Output is correct
47 Correct 95 ms 6536 KB Output is correct
48 Correct 28 ms 4032 KB Output is correct
49 Correct 30 ms 5132 KB Output is correct
50 Correct 105 ms 7036 KB Output is correct
51 Correct 34 ms 4300 KB Output is correct
52 Correct 36 ms 5444 KB Output is correct
53 Correct 103 ms 7464 KB Output is correct
54 Correct 39 ms 4600 KB Output is correct
55 Correct 41 ms 5716 KB Output is correct
56 Correct 122 ms 8080 KB Output is correct
57 Correct 47 ms 4812 KB Output is correct
58 Correct 49 ms 6236 KB Output is correct
59 Correct 149 ms 8564 KB Output is correct
60 Correct 49 ms 5056 KB Output is correct
61 Correct 51 ms 6320 KB Output is correct
62 Correct 148 ms 9068 KB Output is correct
63 Runtime error 149 ms 17860 KB Execution killed with signal 8
64 Correct 200 ms 9104 KB Output is correct
65 Correct 183 ms 9056 KB Output is correct
66 Correct 148 ms 9060 KB Output is correct
67 Runtime error 145 ms 17856 KB Execution killed with signal 8
68 Runtime error 89 ms 16532 KB Execution killed with signal 8
69 Correct 88 ms 8708 KB Output is correct
70 Correct 70 ms 8396 KB Output is correct
71 Correct 69 ms 8452 KB Output is correct
72 Incorrect 57 ms 4848 KB Output isn't correct
73 Incorrect 69 ms 9308 KB Output isn't correct
74 Correct 81 ms 9212 KB Output is correct
75 Correct 99 ms 9292 KB Output is correct
76 Correct 100 ms 8936 KB Output is correct
77 Correct 88 ms 9320 KB Output is correct
78 Runtime error 96 ms 13528 KB Execution killed with signal 8
79 Correct 76 ms 6264 KB Output is correct
80 Correct 90 ms 6364 KB Output is correct
81 Correct 101 ms 6524 KB Output is correct
82 Correct 82 ms 6232 KB Output is correct
83 Runtime error 101 ms 13388 KB Execution killed with signal 8
84 Correct 99 ms 6560 KB Output is correct
85 Correct 96 ms 6724 KB Output is correct
86 Correct 110 ms 6688 KB Output is correct
87 Correct 115 ms 6600 KB Output is correct
88 Runtime error 146 ms 13860 KB Execution killed with signal 8
89 Correct 100 ms 6860 KB Output is correct
90 Correct 123 ms 6900 KB Output is correct
91 Correct 129 ms 6768 KB Output is correct
92 Correct 136 ms 6996 KB Output is correct