Submission #552760

# Submission time Handle Problem Language Result Execution time Memory
552760 2022-04-23T20:19:28 Z Iwanttobreakfree Mecho (IOI09_mecho) C++
54 / 100
367 ms 43708 KB
#include <iostream>
#include <vector>
#include <queue>
using namespace std;
void bfs(queue<int>& q,vector<int>& dist,vector<vector<int>>& g,int b){
    int n=dist.size();
    while(!q.empty()){
        int u=q.front();
        q.pop();
        for(int v:g[u]){
            if(dist[v]==-1&&v!=b){
                dist[v]=dist[u]+1;
                q.push(v);
            }
        }
    }
}
bool pos(int a,int b,int mid,int s,vector<vector<int>>& g,vector<int>& dist){
    int n=dist.size();
    vector<pair<int,int>> d(n,{-1,-1});
    queue<int> q;
    q.push(a);
    //cout<<mid<<'\n';
    if(mid>=dist[a])return false;
    d[a].first=mid;
    d[a].second=-1;
    while(!q.empty()){
        int u=q.front();
        if(u==b)return true;
        q.pop();
        //cout<<d[u].first<<' ';
        for(int v:g[u]){
            if(d[v].first==-1){
                d[v]=d[u];
                d[v].second++;
                if(d[v].second==s){
                    d[v].second=0;
                    d[v].first++;
                }
                if(d[v].first<dist[v])q.push(v);
            }
        }
    }
    return false;
}
int main(){
    int n,s,u,v;
    char c;
    cin>>n>>s;
    vector<vector<int>> g(n*n,vector<int>());
    vector<vector<char>> grid(n,vector<char>(n));
    vector<int> dist(n*n,-1);
    queue<int> q;
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            cin>>grid[i][j];
            if(grid[i][j]=='T')continue;
            else{
                if(i&&grid[i-1][j]!='T'){
                    g[i*n+j].push_back(i*n+j-n);
                    g[i*n+j-n].push_back(i*n+j);
                }
                if(j&&grid[i][j-1]!='T'){
                    g[i*n+j].push_back(i*n+j-1);
                    g[i*n+j-1].push_back(i*n+j);
                }
                if(grid[i][j]=='D'){
                    v=i*n+j;
                    dist[v]=1e9;
                }
                if(grid[i][j]=='M')u=i*n+j;
                if(grid[i][j]=='H'){
                    q.push(i*n+j);
                    dist[i*n+j]=0;
                }
            }
        }
    }
    bfs(q,dist,g,v);
    int l=0,r=1e9,ans=-1;
    while(l<=r){
        int mid=(r+l)/2;
        if(pos(u,v,mid,s,g,dist)){
            l=mid+1;
            ans=mid;
        }
        else r=mid-1;
    }
    cout<<ans;
}

Compilation message

mecho.cpp: In function 'void bfs(std::queue<int>&, std::vector<int>&, std::vector<std::vector<int> >&, int)':
mecho.cpp:6:9: warning: unused variable 'n' [-Wunused-variable]
    6 |     int n=dist.size();
      |         ^
mecho.cpp: In function 'int main()':
mecho.cpp:48:10: warning: unused variable 'c' [-Wunused-variable]
   48 |     char c;
      |          ^
mecho.cpp:83:15: warning: 'v' may be used uninitialized in this function [-Wmaybe-uninitialized]
   83 |         if(pos(u,v,mid,s,g,dist)){
      |            ~~~^~~~~~~~~~~~~~~~~~
mecho.cpp:83:15: warning: 'u' may be used uninitialized in this function [-Wmaybe-uninitialized]
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 256 KB Output isn't correct
2 Incorrect 1 ms 212 KB Output isn't correct
3 Incorrect 0 ms 212 KB Output isn't correct
4 Incorrect 1 ms 212 KB Output isn't correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 335 ms 43708 KB Output is correct
8 Incorrect 1 ms 212 KB Output isn't correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 300 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 340 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Incorrect 1 ms 212 KB Output isn't correct
16 Correct 1 ms 296 KB Output is correct
17 Incorrect 1 ms 340 KB Output isn't correct
18 Correct 1 ms 300 KB Output is correct
19 Incorrect 1 ms 340 KB Output isn't correct
20 Correct 1 ms 296 KB Output is correct
21 Incorrect 1 ms 340 KB Output isn't correct
22 Correct 1 ms 340 KB Output is correct
23 Incorrect 1 ms 432 KB Output isn't correct
24 Correct 1 ms 424 KB Output is correct
25 Incorrect 1 ms 468 KB Output isn't correct
26 Correct 1 ms 428 KB Output is correct
27 Incorrect 2 ms 436 KB Output isn't correct
28 Correct 1 ms 468 KB Output is correct
29 Incorrect 1 ms 468 KB Output isn't correct
30 Correct 1 ms 468 KB Output is correct
31 Incorrect 1 ms 596 KB Output isn't correct
32 Correct 1 ms 596 KB Output is correct
33 Incorrect 17 ms 6760 KB Output isn't correct
34 Correct 19 ms 6788 KB Output is correct
35 Correct 65 ms 7700 KB Output is correct
36 Incorrect 24 ms 8688 KB Output isn't correct
37 Correct 28 ms 8792 KB Output is correct
38 Correct 69 ms 9972 KB Output is correct
39 Incorrect 30 ms 10944 KB Output isn't correct
40 Correct 30 ms 10904 KB Output is correct
41 Correct 98 ms 12516 KB Output is correct
42 Incorrect 38 ms 13388 KB Output isn't correct
43 Correct 40 ms 13320 KB Output is correct
44 Correct 115 ms 15312 KB Output is correct
45 Incorrect 43 ms 16132 KB Output isn't correct
46 Correct 43 ms 16112 KB Output is correct
47 Correct 146 ms 18424 KB Output is correct
48 Incorrect 57 ms 19000 KB Output isn't correct
49 Correct 50 ms 18992 KB Output is correct
50 Correct 175 ms 21832 KB Output is correct
51 Incorrect 63 ms 22352 KB Output isn't correct
52 Correct 62 ms 22368 KB Output is correct
53 Correct 208 ms 25656 KB Output is correct
54 Incorrect 72 ms 25860 KB Output isn't correct
55 Correct 76 ms 25876 KB Output is correct
56 Correct 260 ms 29612 KB Output is correct
57 Incorrect 80 ms 29608 KB Output isn't correct
58 Correct 81 ms 29600 KB Output is correct
59 Correct 307 ms 34084 KB Output is correct
60 Incorrect 105 ms 33600 KB Output isn't correct
61 Correct 95 ms 33624 KB Output is correct
62 Correct 367 ms 38636 KB Output is correct
63 Correct 250 ms 35532 KB Output is correct
64 Correct 326 ms 35556 KB Output is correct
65 Correct 348 ms 35656 KB Output is correct
66 Incorrect 262 ms 35544 KB Output isn't correct
67 Correct 263 ms 35584 KB Output is correct
68 Correct 171 ms 35532 KB Output is correct
69 Correct 169 ms 35508 KB Output is correct
70 Correct 161 ms 35604 KB Output is correct
71 Correct 152 ms 35532 KB Output is correct
72 Correct 142 ms 35548 KB Output is correct
73 Correct 271 ms 43516 KB Output is correct
74 Correct 253 ms 43588 KB Output is correct
75 Correct 262 ms 43580 KB Output is correct
76 Correct 275 ms 43596 KB Output is correct
77 Correct 251 ms 43596 KB Output is correct
78 Correct 276 ms 43596 KB Output is correct
79 Correct 234 ms 43584 KB Output is correct
80 Correct 242 ms 43636 KB Output is correct
81 Correct 235 ms 43540 KB Output is correct
82 Correct 237 ms 43596 KB Output is correct
83 Correct 304 ms 43472 KB Output is correct
84 Correct 266 ms 43444 KB Output is correct
85 Correct 293 ms 43528 KB Output is correct
86 Correct 315 ms 43628 KB Output is correct
87 Correct 278 ms 43620 KB Output is correct
88 Correct 329 ms 43648 KB Output is correct
89 Correct 319 ms 43552 KB Output is correct
90 Correct 327 ms 43560 KB Output is correct
91 Correct 313 ms 43576 KB Output is correct
92 Correct 297 ms 43540 KB Output is correct