답안 #844664

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
844664	2023-09-05T16:24:35 Z	saturina	Mecho (IOI09_mecho)	C++14	100 / 100	691 ms	7516 KB

mecho

//made by Nguyễn Hồng Nam
#include <bits/stdc++.h>
using namespace std;
#define ll int
#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define pll pair<ll,ll>
#define fi first
#define se second
const ll mod = 1e9 + 7,inf = 1e9,mxn = 805;
string s[mxn];
ll n,step,ans = inf,bear[mxn][mxn],bee[mxn][mxn],row[4] = {-1,0,0,1},col[4] = {0,-1,1,0},inf2;
pll start,en;
bool mark[mxn][mxn];
void minz(ll &a,ll b)
{
    if(a > b ) a = b;
}
bool check_bee(ll a,ll b)
{
    if(a >= 0 && a < n && b >= 0 && b < n && s[a][b] != 'T' && s[a][b] != 'D' && s[a][b] != 'H') return true;
    return 0;
}
bool check_bear(ll a,ll b)
{
    if(a >= 0 && a < n && b >= 0 && b < n && s[a][b] != 'T' && s[a][b] != 'H' && mark[a][b] == 0) return true;
    return 0;
}
void bfs_hive(ll i,ll j)
{
    if(bee[i][j] == 0) return;
    memset(mark,false,sizeof mark);
    bee[i][j] = 0;
    mark[i][j] = 1;
    queue<pll> q;
    q.push({i,j});
    while(!q.empty())
    {
        pll u = q.front();
        q.pop();
        mark[u.fi][u.se] = 1;
        for(ll k = 0; k < 4; k++)
        {
            ll a = u.fi + row[k],b = u.se + col[k];
            if(check_bee(a,b) && bee[u.fi][u.se] + 1 < bee[a][b])
            {
                bee[a][b] = bee[u.fi][u.se] + 1;
                mark[a][b] = 1;
                q.push({a,b});
            }
        }
    }
}
void bfs(ll i,ll j )
{
    memset(mark,0,sizeof mark);
    mark[i][j] = 1;
    queue<pll> q;
    q.push({i,j});
    bear[i][j] = 0;
    while(!q.empty())
    {
        pll u = q.front();
        mark[u.fi][u.se] = 1;
        q.pop();
        for(ll k = 0; k < 4; k++)
        {
            ll a = u.fi + row[k],b = u.se + col[k];
            if(check_bear(a,b))
            {
                mark[a][b] = 1;
                bear[a][b] = bear[u.fi][u.se] + 1;
                q.push({a,b});
                //if(a == en.fi && b == en.se) return;
            }
        }
    }
}
bool f(ll x)
{
    if(x >= bee[start.fi][start.se]) return 0;
    memset(mark,0,sizeof mark);
    mark[start.fi][start.se] = 1;
    queue<pair<pll,ll>>q;
    q.push({start,0});
    while(!q.empty())
    {
        auto u = q.front();
        q.pop();
        mark[u.fi.fi][u.fi.se] = 1;
        for(ll i = 0; i < 4; i++)
        {
            ll a = u.fi.fi + row[i],b = u.fi.se + col[i];
            if(mark[a][b] == 0 && a >= 0 && a < n && b >= 0 && b < n && s[a][b] != 'T' && s[a][b] != 'H' && (x + ((u.se + 1) / step)) < bee[a][b])
            {
                mark[a][b] = 1;
                if(mark[en.fi][en.se] == 1) return 1;
                q.push({{a,b},u.se + 1});
            }
        }
    }
    if(mark[en.fi][en.se] == 1) return 1;
    return 0;
}
int main()
{
#define taskname "mecho"
    if (fopen(taskname".inp", "r"))
    {
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> step;
    for(ll i = 0; i < n; i++)
    {
        cin >> s[i];
        for(ll j = 0; j < n; j++)
        {
            if(s[i][j] == 'M') start = {i,j};
            else if(s[i][j] == 'D') en = {i,j};
        }
    }
    memset(bee,60,sizeof bee);
    inf2 = bee[0][0];
    for(ll i = 0; i < n; i++)
    {
        for(ll j = 0; j < n; j++) if(s[i][j] == 'H') bfs_hive(i,j);
    }
    bfs(start.fi,start.se);
    ll lf = 0,rt = inf - 1;
    while(lf <= rt)
    {
        ll mid = (lf + rt)/2;
        if(f(mid))
        {
            ans = mid;
            lf = mid + 1;
        }
        else rt = mid - 1;
    }
//    for(ll i = 0; i < n; i++)
//    {
//        for(ll j = 0; j < n; j++)
//        {
//            if(bee[i][j] != inf2) cout << bee[i][j] << ' ';
//            else cout << "-1 ";
//        }
//        cout << '\n';
//    }
    bee[en.fi][en.se] = inf2;
//    for(ll i = 0; i < n; i++)
//    {
//        for(ll j = 0; j < n; j++)
//        {
//            if(bee[i][j] != inf2) cout << bear[i][j] << ' ';
//            else cout << "-1 ";
//        }
//        cout << '\n';
//    }
    if(ans == inf) cout << "-1\n";
    else cout << ans << '\n';
    return 0;
}

Compilation message

mecho.cpp: In function 'int main()':
mecho.cpp:110:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  110 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
mecho.cpp:111:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  111 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1

100.0 / 100.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	4700 KB	Output is correct
2	Correct	1 ms	4700 KB	Output is correct
3	Correct	1 ms	4700 KB	Output is correct
4	Correct	1 ms	4700 KB	Output is correct
5	Correct	1 ms	4700 KB	Output is correct
6	Correct	1 ms	4700 KB	Output is correct
7	Correct	146 ms	7448 KB	Output is correct
8	Correct	1 ms	4696 KB	Output is correct
9	Correct	1 ms	4696 KB	Output is correct
10	Correct	1 ms	4700 KB	Output is correct
11	Correct	1 ms	4700 KB	Output is correct
12	Correct	1 ms	4700 KB	Output is correct
13	Correct	3 ms	4700 KB	Output is correct
14	Correct	3 ms	4700 KB	Output is correct
15	Correct	1 ms	4700 KB	Output is correct
16	Correct	1 ms	4696 KB	Output is correct
17	Correct	1 ms	4700 KB	Output is correct
18	Correct	1 ms	4700 KB	Output is correct
19	Correct	1 ms	4700 KB	Output is correct
20	Correct	1 ms	4700 KB	Output is correct
21	Correct	1 ms	4700 KB	Output is correct
22	Correct	1 ms	4700 KB	Output is correct
23	Correct	1 ms	4700 KB	Output is correct
24	Correct	1 ms	4700 KB	Output is correct
25	Correct	1 ms	4700 KB	Output is correct
26	Correct	1 ms	4700 KB	Output is correct
27	Correct	1 ms	4700 KB	Output is correct
28	Correct	1 ms	4700 KB	Output is correct
29	Correct	1 ms	4700 KB	Output is correct
30	Correct	1 ms	4700 KB	Output is correct
31	Correct	1 ms	4700 KB	Output is correct
32	Correct	1 ms	4700 KB	Output is correct
33	Correct	3 ms	4956 KB	Output is correct
34	Correct	3 ms	4956 KB	Output is correct
35	Correct	14 ms	4960 KB	Output is correct
36	Correct	4 ms	5212 KB	Output is correct
37	Correct	4 ms	5212 KB	Output is correct
38	Correct	18 ms	5212 KB	Output is correct
39	Correct	4 ms	5336 KB	Output is correct
40	Correct	5 ms	5464 KB	Output is correct
41	Correct	23 ms	5472 KB	Output is correct
42	Correct	5 ms	5720 KB	Output is correct
43	Correct	6 ms	5468 KB	Output is correct
44	Correct	31 ms	5740 KB	Output is correct
45	Correct	6 ms	5980 KB	Output is correct
46	Correct	7 ms	5980 KB	Output is correct
47	Correct	36 ms	5980 KB	Output is correct
48	Correct	7 ms	6236 KB	Output is correct
49	Correct	8 ms	6072 KB	Output is correct
50	Correct	43 ms	6272 KB	Output is correct
51	Correct	8 ms	6492 KB	Output is correct
52	Correct	9 ms	6492 KB	Output is correct
53	Correct	57 ms	6532 KB	Output is correct
54	Correct	9 ms	6748 KB	Output is correct
55	Correct	16 ms	6764 KB	Output is correct
56	Correct	58 ms	6828 KB	Output is correct
57	Correct	10 ms	6904 KB	Output is correct
58	Correct	13 ms	7004 KB	Output is correct
59	Correct	67 ms	7004 KB	Output is correct
60	Correct	13 ms	7516 KB	Output is correct
61	Correct	13 ms	7260 KB	Output is correct
62	Correct	78 ms	7448 KB	Output is correct
63	Correct	122 ms	7504 KB	Output is correct
64	Correct	186 ms	7436 KB	Output is correct
65	Correct	171 ms	7436 KB	Output is correct
66	Correct	136 ms	7312 KB	Output is correct
67	Correct	127 ms	7440 KB	Output is correct
68	Correct	198 ms	7296 KB	Output is correct
69	Correct	195 ms	7252 KB	Output is correct
70	Correct	196 ms	7316 KB	Output is correct
71	Correct	186 ms	7248 KB	Output is correct
72	Correct	184 ms	7304 KB	Output is correct
73	Correct	564 ms	7360 KB	Output is correct
74	Correct	598 ms	7308 KB	Output is correct
75	Correct	691 ms	7300 KB	Output is correct
76	Correct	663 ms	7308 KB	Output is correct
77	Correct	684 ms	7312 KB	Output is correct
78	Correct	558 ms	7300 KB	Output is correct
79	Correct	548 ms	7308 KB	Output is correct
80	Correct	565 ms	7300 KB	Output is correct
81	Correct	521 ms	7304 KB	Output is correct
82	Correct	503 ms	7252 KB	Output is correct
83	Correct	210 ms	7320 KB	Output is correct
84	Correct	207 ms	7324 KB	Output is correct
85	Correct	213 ms	7248 KB	Output is correct
86	Correct	213 ms	7304 KB	Output is correct
87	Correct	211 ms	7248 KB	Output is correct
88	Correct	169 ms	7308 KB	Output is correct
89	Correct	166 ms	7308 KB	Output is correct
90	Correct	177 ms	7432 KB	Output is correct
91	Correct	169 ms	7316 KB	Output is correct
92	Correct	170 ms	7248 KB	Output is correct