oj.uz

Submission #500056

# Submission time Handle Problem Language Result Execution time Memory
500056 2021-12-30T09:56:00 Z Nartifact Mecho (IOI09_mecho) C++14
95 / 100
 207 ms 4772 KB 
#include <bits/stdc++.h>
using namespace std;

#define forinc(i,a,b) for(int i=a;i<=b;++i)
#define fordec(i,a,b) for(int i=a;i>=b;--i)
#define pb push_back
#define eb emplace_back
#define pii pair <int,int>
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int N = 888, inf = 1e9 + 69;
const int H[] = {1, 0, -1, 0};
const int C[] = {0, 1, 0, -1};
int n, s;
char a[N][N];
int t[N][N];
bool cx[N][N];
pii sta, fin;

bool valid (const int& x, const int& y)
{
    return x && y && x <= n && y <= n
          && a[x][y] != 'T';
}

struct adt {int x, y, step;};

bool ok (const int& tg)
{
    queue <adt> q;
    forinc(i,1,n) forinc(j,1,n) cx[i][j] = 0;
    q.push({sta.fi, sta.se, 0});
    cx[sta.fi][sta.se] = 1;
    while(q.size()) {
        auto tmp = q.front(); q.pop();
        if(tmp.x == fin.fi && tmp.y == fin.se) return 1;
        forinc(i,0,3) {
            int nh = tmp.x + H[i];
            int nc = tmp.y + C[i];
            if(valid(nh, nc) && !cx[nh][nc] && (tmp.step + 1) / s < t[nh][nc] - tg) {
                q.push({nh, nc, tmp.step + 1});
                cx[nh][nc] = 1;
            }
        }
    }
    return 0;
}

void solve ()
{
    queue <pii> q;
    forinc(i,1,n) forinc(j,1,n) {
        t[i][j] = inf;
        if(a[i][j] == 'H') {
            q.push({i, j});
            t[i][j] = 0;
        }
        else if(a[i][j] == 'M') sta = {i, j};
        else if(a[i][j] == 'D') fin = {i, j};
    }

    // bfs bee
    while(q.size()) {
        auto x = q.front(); q.pop();
        forinc(i,0,3) {
            int nh = x.fi + H[i];
            int nc = x.se + C[i];
            if(valid(nh, nc) && t[nh][nc] > t[x.fi][x.se] + 1) {
                t[nh][nc] = t[x.fi][x.se] + 1;
                q.push({nh, nc});
            }
        }
    }
	t[fin.fi][fin.se] = inf;
    // binary search
    int l = 0, r = t[sta.fi][sta.se] - 1, ans = -1;
    while(l <= r) {
        int mid = l + r >> 1;
        if(ok(mid)) {
            ans = mid;
            l = mid + 1;
        }
        else r = mid - 1;
    }
    cout << ans;
}

void read ()
{
    cin >> n >> s;
    forinc(i,1,n) forinc(j,1,n)
        cin >> a[i][j];
    solve();
}

main ()
{
	#define task "ioi09_mecho"
	cin.tie(0) -> sync_with_stdio(0);
	if(fopen (task ".inp", "r")) {
		freopen (task ".inp", "r", stdin);
		freopen (task ".out", "w", stdout);
	}
    read();
	return 0;
}

Compilation message

mecho.cpp: In function 'void solve()':
mecho.cpp:82:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   82 |         int mid = l + r >> 1;
      |                   ~~^~~
mecho.cpp: At global scope:
mecho.cpp:100:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  100 | main ()
      | ^~~~
mecho.cpp: In function 'int main()':
mecho.cpp:105:11: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  105 |   freopen (task ".inp", "r", stdin);
      |   ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
mecho.cpp:106:11: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  106 |   freopen (task ".out", "w", stdout);
      |   ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
95.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 0 ms 332 KB Output is correct
6 Correct 0 ms 332 KB Output is correct
7 Correct 106 ms 4592 KB Output is correct
8 Correct 0 ms 332 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct
12 Incorrect 1 ms 588 KB Output isn't correct
13 Correct 1 ms 588 KB Output is correct
14 Correct 1 ms 588 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 0 ms 332 KB Output is correct
17 Correct 0 ms 460 KB Output is correct
18 Correct 1 ms 460 KB Output is correct
19 Correct 0 ms 460 KB Output is correct
20 Correct 0 ms 460 KB Output is correct
21 Correct 0 ms 460 KB Output is correct
22 Correct 0 ms 460 KB Output is correct
23 Correct 0 ms 588 KB Output is correct
24 Correct 1 ms 588 KB Output is correct
25 Correct 1 ms 588 KB Output is correct
26 Correct 1 ms 588 KB Output is correct
27 Correct 1 ms 588 KB Output is correct
28 Correct 1 ms 588 KB Output is correct
29 Correct 1 ms 588 KB Output is correct
30 Correct 1 ms 588 KB Output is correct
31 Correct 1 ms 716 KB Output is correct
32 Correct 1 ms 716 KB Output is correct
33 Correct 4 ms 2124 KB Output is correct
34 Correct 4 ms 2124 KB Output is correct
35 Correct 17 ms 2108 KB Output is correct
36 Correct 5 ms 2380 KB Output is correct
37 Correct 5 ms 2380 KB Output is correct
38 Correct 22 ms 2424 KB Output is correct
39 Correct 6 ms 2636 KB Output is correct
40 Correct 6 ms 2656 KB Output is correct
41 Correct 29 ms 2672 KB Output is correct
42 Correct 7 ms 2892 KB Output is correct
43 Correct 6 ms 2832 KB Output is correct
44 Correct 39 ms 2920 KB Output is correct
45 Correct 9 ms 3148 KB Output is correct
46 Correct 9 ms 3184 KB Output is correct
47 Correct 55 ms 3116 KB Output is correct
48 Correct 9 ms 3404 KB Output is correct
49 Correct 9 ms 3404 KB Output is correct
50 Correct 54 ms 3440 KB Output is correct
51 Correct 11 ms 3660 KB Output is correct
52 Correct 11 ms 3664 KB Output is correct
53 Correct 63 ms 3716 KB Output is correct
54 Correct 12 ms 3916 KB Output is correct
55 Correct 12 ms 3896 KB Output is correct
56 Correct 86 ms 3888 KB Output is correct
57 Correct 14 ms 4196 KB Output is correct
58 Correct 14 ms 4192 KB Output is correct
59 Correct 95 ms 4300 KB Output is correct
60 Correct 17 ms 4408 KB Output is correct
61 Correct 15 ms 4428 KB Output is correct
62 Correct 102 ms 4456 KB Output is correct
63 Correct 98 ms 4468 KB Output is correct
64 Correct 207 ms 4444 KB Output is correct
65 Correct 159 ms 4492 KB Output is correct
66 Correct 115 ms 4484 KB Output is correct
67 Correct 111 ms 4484 KB Output is correct
68 Correct 45 ms 4420 KB Output is correct
69 Correct 36 ms 4420 KB Output is correct
70 Correct 38 ms 4464 KB Output is correct
71 Correct 34 ms 4516 KB Output is correct
72 Correct 27 ms 4472 KB Output is correct
73 Correct 37 ms 4728 KB Output is correct
74 Correct 72 ms 4764 KB Output is correct
75 Correct 69 ms 4760 KB Output is correct
76 Correct 78 ms 4760 KB Output is correct
77 Correct 79 ms 4772 KB Output is correct
78 Correct 80 ms 4732 KB Output is correct
79 Correct 64 ms 4732 KB Output is correct
80 Correct 62 ms 4732 KB Output is correct
81 Correct 90 ms 4736 KB Output is correct
82 Correct 59 ms 4692 KB Output is correct
83 Correct 74 ms 4652 KB Output is correct
84 Correct 75 ms 4652 KB Output is correct
85 Correct 110 ms 4692 KB Output is correct
86 Correct 72 ms 4696 KB Output is correct
87 Correct 67 ms 4700 KB Output is correct
88 Correct 79 ms 4640 KB Output is correct
89 Correct 71 ms 4612 KB Output is correct
90 Correct 82 ms 4676 KB Output is correct
91 Correct 79 ms 4644 KB Output is correct
92 Correct 79 ms 4612 KB Output is correct