Submission #545004

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
545004	2022-04-03T10:09:40 Z	MilosMilutinovic	Mecho (IOI09_mecho)	C++14	100 / 100	166 ms	6304 KB

mecho

#include<bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
#define mp make_pair

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

template<typename T> bool chkmin(T&x,T y){return x>y?x=y,1:0;}
template<typename T> bool chkmax(T&x,T y){return x<y?x=y,1:0;}

int n,s,sx,sy,ex,ey,dist[805][805],dis[805][805];
char base[805][805];
const int dir[4][2]={0,1,0,-1,1,0,-1,0};

void bfs(){
	memset(dist,-1,sizeof dist);
	queue<pii> que;
	for(int i=1;i<=n;i++) for(int j=1;j<=n;j++) if(base[i][j]=='H') que.push(mp(i,j)),dist[i][j]=0;
	while(!que.empty()){
		int i=que.front().fi;
		int j=que.front().se;
		que.pop();
		for(int k=0;k<4;k++){
			int ni=i+dir[k][0];
			int nj=j+dir[k][1];
			if(ni>=1&&ni<=n&&nj>=1&&nj<=n&&(base[ni][nj]=='G'||base[ni][nj]=='M')&dist[ni][nj]==-1){
				que.push(mp(ni,nj)); dist[ni][nj]=dist[i][j]+s;
			}
		}
	}
}

bool check(int t){
	if(dist[sx][sy]<=t*s) return false;
	memset(dis,-1,sizeof dis);
	queue<pii> que;
	que.push(mp(sx,sy)); dis[sx][sy]=t*s;
	while(!que.empty()){
		int i=que.front().fi;
		int j=que.front().se;
		que.pop();
		for(int k=0;k<4;k++){
			int ni=i+dir[k][0];
			int nj=j+dir[k][1];
			if(ni>=1&&ni<=n&&nj>=1&&nj<=n&&dis[ni][nj]==-1&&(base[ni][nj]=='D'||(base[ni][nj]=='G'&&dist[ni][nj]>dis[i][j]+1))){
				que.push(mp(ni,nj)); dis[ni][nj]=dis[i][j]+1;
			}
		}
	}
	return dis[ex][ey]!=-1;
}

int main(){
	scanf("%d%d",&n,&s);
	for(int i=1;i<=n;i++){
		scanf("%s",base[i]+1);
		for(int j=1;j<=n;j++){
			if(base[i][j]=='M') sx=i,sy=j;
			if(base[i][j]=='D') ex=i,ey=j;
		}
	}
	bfs();
	int l=-1,r=n*n+5,ans=-1;
	while(l<=r){
		int m=(l+r)/2;
		if(check(m)) ans=m,l=m+1; else r=m-1;
	}
	printf("%d",ans);
	return 0;
}

Compilation message

mecho.cpp: In function 'void bfs()':
mecho.cpp:33:86: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   33 |    if(ni>=1&&ni<=n&&nj>=1&&nj<=n&&(base[ni][nj]=='G'||base[ni][nj]=='M')&dist[ni][nj]==-1){
      |                                                                          ~~~~~~~~~~~~^~~~
mecho.cpp: In function 'int main()':
mecho.cpp:61:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   61 |  scanf("%d%d",&n,&s);
      |  ~~~~~^~~~~~~~~~~~~~
mecho.cpp:63:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |   scanf("%s",base[i]+1);
      |   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	2 ms	5332 KB	Output is correct
2	Correct	3 ms	5332 KB	Output is correct
3	Correct	4 ms	5332 KB	Output is correct
4	Correct	3 ms	5332 KB	Output is correct
5	Correct	3 ms	5332 KB	Output is correct
6	Correct	3 ms	5332 KB	Output is correct
7	Correct	81 ms	6012 KB	Output is correct
8	Correct	3 ms	5332 KB	Output is correct
9	Correct	4 ms	5332 KB	Output is correct
10	Correct	2 ms	5332 KB	Output is correct
11	Correct	3 ms	5332 KB	Output is correct
12	Correct	3 ms	5332 KB	Output is correct
13	Correct	2 ms	5332 KB	Output is correct
14	Correct	3 ms	5332 KB	Output is correct
15	Correct	3 ms	5332 KB	Output is correct
16	Correct	3 ms	5332 KB	Output is correct
17	Correct	3 ms	5332 KB	Output is correct
18	Correct	2 ms	5332 KB	Output is correct
19	Correct	3 ms	5332 KB	Output is correct
20	Correct	3 ms	5332 KB	Output is correct
21	Correct	3 ms	5332 KB	Output is correct
22	Correct	3 ms	5332 KB	Output is correct
23	Correct	3 ms	5376 KB	Output is correct
24	Correct	3 ms	5332 KB	Output is correct
25	Correct	3 ms	5400 KB	Output is correct
26	Correct	3 ms	5332 KB	Output is correct
27	Correct	3 ms	5332 KB	Output is correct
28	Correct	3 ms	5332 KB	Output is correct
29	Correct	4 ms	5332 KB	Output is correct
30	Correct	4 ms	5332 KB	Output is correct
31	Correct	3 ms	5332 KB	Output is correct
32	Correct	3 ms	5336 KB	Output is correct
33	Correct	6 ms	5588 KB	Output is correct
34	Correct	6 ms	5652 KB	Output is correct
35	Correct	19 ms	5656 KB	Output is correct
36	Correct	6 ms	5588 KB	Output is correct
37	Correct	7 ms	5588 KB	Output is correct
38	Correct	24 ms	5588 KB	Output is correct
39	Correct	7 ms	5716 KB	Output is correct
40	Correct	9 ms	5716 KB	Output is correct
41	Correct	29 ms	5732 KB	Output is correct
42	Correct	9 ms	5664 KB	Output is correct
43	Correct	11 ms	5716 KB	Output is correct
44	Correct	49 ms	5696 KB	Output is correct
45	Correct	10 ms	5716 KB	Output is correct
46	Correct	13 ms	5808 KB	Output is correct
47	Correct	45 ms	5708 KB	Output is correct
48	Correct	10 ms	5844 KB	Output is correct
49	Correct	12 ms	5820 KB	Output is correct
50	Correct	52 ms	5840 KB	Output is correct
51	Correct	12 ms	5844 KB	Output is correct
52	Correct	14 ms	5844 KB	Output is correct
53	Correct	58 ms	5844 KB	Output is correct
54	Correct	15 ms	5828 KB	Output is correct
55	Correct	22 ms	5844 KB	Output is correct
56	Correct	82 ms	5916 KB	Output is correct
57	Correct	15 ms	5844 KB	Output is correct
58	Correct	22 ms	5964 KB	Output is correct
59	Correct	100 ms	5952 KB	Output is correct
60	Correct	16 ms	5908 KB	Output is correct
61	Correct	23 ms	5904 KB	Output is correct
62	Correct	166 ms	5992 KB	Output is correct
63	Correct	86 ms	5972 KB	Output is correct
64	Correct	133 ms	5988 KB	Output is correct
65	Correct	159 ms	5984 KB	Output is correct
66	Correct	114 ms	5996 KB	Output is correct
67	Correct	100 ms	5992 KB	Output is correct
68	Correct	40 ms	5924 KB	Output is correct
69	Correct	53 ms	6016 KB	Output is correct
70	Correct	37 ms	5940 KB	Output is correct
71	Correct	31 ms	5932 KB	Output is correct
72	Correct	24 ms	5928 KB	Output is correct
73	Correct	33 ms	6176 KB	Output is correct
74	Correct	54 ms	6304 KB	Output is correct
75	Correct	55 ms	6148 KB	Output is correct
76	Correct	58 ms	6164 KB	Output is correct
77	Correct	54 ms	6164 KB	Output is correct
78	Correct	68 ms	6236 KB	Output is correct
79	Correct	40 ms	6124 KB	Output is correct
80	Correct	53 ms	6164 KB	Output is correct
81	Correct	59 ms	6240 KB	Output is correct
82	Correct	55 ms	6228 KB	Output is correct
83	Correct	71 ms	6116 KB	Output is correct
84	Correct	75 ms	6200 KB	Output is correct
85	Correct	81 ms	6112 KB	Output is correct
86	Correct	64 ms	6204 KB	Output is correct
87	Correct	75 ms	6200 KB	Output is correct
88	Correct	83 ms	6144 KB	Output is correct
89	Correct	103 ms	6056 KB	Output is correct
90	Correct	88 ms	6052 KB	Output is correct
91	Correct	74 ms	6152 KB	Output is correct
92	Correct	80 ms	6144 KB	Output is correct