Submission #957759

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
957759	2024-04-04T09:21:21 Z	hirayuu_oj	Mecho (IOI09_mecho)	C++17	100 / 100	153 ms	11356 KB

mecho

#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0; i<(n); i++)
#define rep2(i,a,b) for(int i=a; i<(b); i++)
#define all(x) x.begin(),x.end()
using ll=long long;
const ll INF=1LL<<60;
const int four[5]={0,1,0,-1,0};

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    ll s;
    cin>>n>>s;
    vector<string> forest(n);
    rep(i,n){
        cin>>forest[i];
    }
    vector<vector<ll>> bee(n,vector<ll>(n,INF));
    queue<pair<int,int>> vert;
    rep(i,n){
        rep(j,n){
            if(forest[i][j]=='H'){
                bee[i][j]=0;
                vert.push({i,j});
            }
        }
    }
    while(!vert.empty()){
        int x,y;
        tie(x,y)=vert.front();
        vert.pop();
        rep(i,4){
            int nx=x+four[i],ny=y+four[i+1];
            if(nx<0 or n<=nx or ny<0 or n<=ny){
                continue;
            }
            if(forest[nx][ny]!='G' and forest[nx][ny]!='M'){
                continue;
            }
            if(bee[nx][ny]>bee[x][y]+1){
                bee[nx][ny]=bee[x][y]+1;
                vert.push({nx,ny});
            }
        }
    }
    int hx,hy;
    ll ok=-1,ng;
    rep(i,n){
        rep(j,n){
            if(forest[i][j]=='D'){
                hx=i;
                hy=j;
            }
            if(forest[i][j]=='M'){
                ng=bee[i][j];
            }
        }
    }
    vector<vector<ll>> dist(n,vector<ll>(n));
    while(ng-ok>1){
        ll mid=(ok+ng)>>1;
        rep(i,n){
            rep(j,n){
                if(forest[i][j]=='M'){
                    dist[i][j]=mid*s;
                    vert.push({i,j});
                }
                else{
                    dist[i][j]=INF;
                }
            }
        }
        bool can=false;
        while(!vert.empty()){
            int x,y;
            tie(x,y)=vert.front();
            vert.pop();
            rep(i,4){
                int nx=x+four[i],ny=y+four[i+1];
                if(nx<0 or n<=nx or ny<0 or n<=ny){
                    continue;
                }
                if(forest[nx][ny]=='D'){
                    can=true;
                }
                if(forest[nx][ny]!='G'){
                    continue;
                }
                if((dist[x][y]+1LL)/s>=bee[nx][ny]){
                    continue;
                }
                if(dist[nx][ny]>dist[x][y]+1){
                    dist[nx][ny]=dist[x][y]+1;
                    vert.push({nx,ny});
                }
            }
        }
        if(can){
            ok=mid;
        }
        else{
            ng=mid;
        }
    }
    cout<<ok<<"\n";
}

Compilation message

mecho.cpp: In function 'int main()':
mecho.cpp:48:9: warning: variable 'hx' set but not used [-Wunused-but-set-variable]
   48 |     int hx,hy;
      |         ^~
mecho.cpp:48:12: warning: variable 'hy' set but not used [-Wunused-but-set-variable]
   48 |     int hx,hy;
      |            ^~
mecho.cpp:63:19: warning: 'ng' may be used uninitialized in this function [-Wmaybe-uninitialized]
   63 |         ll mid=(ok+ng)>>1;
      |                ~~~^~~~

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	344 KB	Output is correct
2	Correct	0 ms	344 KB	Output is correct
3	Correct	1 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	88 ms	11244 KB	Output is correct
8	Correct	0 ms	348 KB	Output is correct
9	Correct	1 ms	348 KB	Output is correct
10	Correct	0 ms	344 KB	Output is correct
11	Correct	1 ms	348 KB	Output is correct
12	Correct	0 ms	348 KB	Output is correct
13	Correct	1 ms	344 KB	Output is correct
14	Correct	1 ms	348 KB	Output is correct
15	Correct	1 ms	344 KB	Output is correct
16	Correct	0 ms	344 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	348 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	1 ms	348 KB	Output is correct
24	Correct	1 ms	348 KB	Output is correct
25	Correct	1 ms	344 KB	Output is correct
26	Correct	1 ms	504 KB	Output is correct
27	Correct	1 ms	344 KB	Output is correct
28	Correct	1 ms	348 KB	Output is correct
29	Correct	1 ms	348 KB	Output is correct
30	Correct	1 ms	348 KB	Output is correct
31	Correct	1 ms	348 KB	Output is correct
32	Correct	1 ms	344 KB	Output is correct
33	Correct	6 ms	2396 KB	Output is correct
34	Correct	6 ms	2396 KB	Output is correct
35	Correct	19 ms	2396 KB	Output is correct
36	Correct	7 ms	3164 KB	Output is correct
37	Correct	8 ms	3164 KB	Output is correct
38	Correct	26 ms	3412 KB	Output is correct
39	Correct	10 ms	3672 KB	Output is correct
40	Correct	12 ms	3676 KB	Output is correct
41	Correct	32 ms	3676 KB	Output is correct
42	Correct	12 ms	4444 KB	Output is correct
43	Correct	12 ms	4696 KB	Output is correct
44	Correct	42 ms	4664 KB	Output is correct
45	Correct	14 ms	5468 KB	Output is correct
46	Correct	19 ms	5468 KB	Output is correct
47	Correct	64 ms	5468 KB	Output is correct
48	Correct	17 ms	6492 KB	Output is correct
49	Correct	17 ms	6388 KB	Output is correct
50	Correct	57 ms	6488 KB	Output is correct
51	Correct	20 ms	7512 KB	Output is correct
52	Correct	21 ms	7516 KB	Output is correct
53	Correct	69 ms	7572 KB	Output is correct
54	Correct	24 ms	8540 KB	Output is correct
55	Correct	23 ms	8540 KB	Output is correct
56	Correct	94 ms	8728 KB	Output is correct
57	Correct	26 ms	9816 KB	Output is correct
58	Correct	28 ms	9820 KB	Output is correct
59	Correct	98 ms	9820 KB	Output is correct
60	Correct	30 ms	11108 KB	Output is correct
61	Correct	32 ms	11100 KB	Output is correct
62	Correct	145 ms	11100 KB	Output is correct
63	Correct	96 ms	11220 KB	Output is correct
64	Correct	153 ms	11100 KB	Output is correct
65	Correct	146 ms	11220 KB	Output is correct
66	Correct	114 ms	11356 KB	Output is correct
67	Correct	100 ms	11100 KB	Output is correct
68	Correct	44 ms	11100 KB	Output is correct
69	Correct	39 ms	11072 KB	Output is correct
70	Correct	37 ms	11100 KB	Output is correct
71	Correct	31 ms	11100 KB	Output is correct
72	Correct	40 ms	11060 KB	Output is correct
73	Correct	38 ms	11092 KB	Output is correct
74	Correct	68 ms	11064 KB	Output is correct
75	Correct	61 ms	11072 KB	Output is correct
76	Correct	65 ms	11276 KB	Output is correct
77	Correct	91 ms	11344 KB	Output is correct
78	Correct	76 ms	11256 KB	Output is correct
79	Correct	61 ms	11100 KB	Output is correct
80	Correct	69 ms	11268 KB	Output is correct
81	Correct	68 ms	11272 KB	Output is correct
82	Correct	71 ms	11280 KB	Output is correct
83	Correct	87 ms	11096 KB	Output is correct
84	Correct	80 ms	11088 KB	Output is correct
85	Correct	71 ms	11096 KB	Output is correct
86	Correct	95 ms	11260 KB	Output is correct
87	Correct	72 ms	11100 KB	Output is correct
88	Correct	87 ms	11252 KB	Output is correct
89	Correct	90 ms	11256 KB	Output is correct
90	Correct	93 ms	11256 KB	Output is correct
91	Correct	87 ms	11204 KB	Output is correct
92	Correct	116 ms	11252 KB	Output is correct