Submission #1103064

# Submission time Handle Problem Language Result Execution time Memory
1103064 2024-10-19T19:22:51 Z ef10 Mecho (IOI09_mecho) C++17
32 / 100
1000 ms 65536 KB
// Source: https://usaco.guide/general/io

#include <bits/stdc++.h>
using namespace std;

int N,S;
string M[1001];
struct node {
	int hd;
	int md;
	int hop;
};
bool v[1001][1001];
node all[1001][1001];
pair<int,int> m;

bool work(int e) {
	for (int i = 0; i < N; i++) {
		for (int j = 0; j < N; j++) {
			all[i][j].md = -1;
		}
	}

	queue<pair<int,int> > q;
	q.push(m);
	all[m.first][m.second].md = e;
	all[m.first][m.second].hop = 0;
	if (all[m.first][m.second].hd != -1 && all[m.first][m.second].hd <= e) return false;
	while (!q.empty()) {
		auto c = q.front();
						//cout << "handling " << c.first << "/" << c.second << "/" << all[c.first][c.second].md << endl;
		int cost = all[c.first][c.second].md+1;
		q.pop();
		queue<tuple<int,int,int> > tq;
		tq.push(make_tuple(c.first,c.second,0));
		while (!tq.empty()) {
			auto tc = tq.front();
			//cout << "    tq " << get<0>(tc) << "/" << get<1>(tc) << "/" << get<2>(tc) << endl;
			tq.pop();
			int hop = get<2>(tc)+1;
			if (hop > S) continue;
			for (auto i : {-1,1}) {
				for (int j = 0; j <= 1; j++) {
					int ti = j ? get<0>(tc) : (get<0>(tc)+i);
					int tj = j ? (get<1>(tc)+i) : (get<1>(tc));
					if (ti < 0 || ti >= N || tj < 0 || tj >= N) continue;
					//cout << "          " << ti << "/" << tj << " " << endl;
					if (M[ti][tj] == 'T') continue;
					if (all[ti][tj].md >= 0
						&& (all[ti][tj].md < cost || (all[ti][tj].md == cost && all[ti][tj].hop <= hop))) continue;
					if (all[ti][tj].hd >= 0 && all[ti][tj].hd < cost) continue;
					if (M[ti][tj] == 'D') return true;
					if (hop == S && all[ti][tj].hd >= 0 && all[ti][tj].hd == cost) continue;
					//cout << "          " << ti << "/" << tj << "/" << hop << " passed" << endl;
					all[ti][tj].md = cost;
					all[ti][tj].hop = hop;
					if (all[ti][tj].hd > cost) {
						q.push(make_pair(ti,tj));
						//cout << "       add q " << ti << "/" << tj << "/" << cost << endl;
					}
					if (hop == S) continue;
					tq.push(make_tuple(ti,tj,hop));
				}
			}
		}
		/*for (int i = 0; i < N; i++) {
			for (int j = 0; j < N; j++) {
				cout << all[i][j].md << "/" << all[i][j].hop << " ";
			}
			cout << endl;
		}*/
	}
	return false;
}

int solve() {
	int lo = 0, hi = 2*N;
		// if none of the values in the range work, return lo - 1
	lo--;
	while (lo < hi) {
		// find the middle of the current range (rounding up)
		int mid = lo + (hi - lo + 1) / 2;
		//cout << "mid: " << mid << ", " << lo << "/" << hi;
		if (work(mid)) {
			//cout << " worked" << endl;
			// if mid works, then all numbers smaller than mid also work
			lo = mid;
		} else {
			//cout << " not work" << endl;
			// if mid does not work, greater values would not work either
			hi = mid - 1;
		}
	}
	return lo;
}

int main() {
	cin >> N >> S;
	for (int i = 0; i < N; i++) {
		for (int j = 0; j < N; j++) {
			all[i][j].hd = -1;
		}
	}
	queue<pair<int,int> > q;
	for (int i = 0; i < N; i++) {
		cin >> M[i];
		for (int j = 0; j < N; j++) {
			if (M[i][j] == 'H') {
				all[i][j].hd = 0;
				q.push(make_pair(i,j));
			} else if (M[i][j] == 'M') {
				m = make_pair(i,j);
			}
		}
	}
	while (!q.empty()) {
		auto c = q.front();
		int cost = all[c.first][c.second].hd+1;
		q.pop();
		for (auto i : {-1,1}) {
			for (int j = 0; j <= 1; j++) {
				int ti = j ? c.first : c.first+i;
				int tj = j ? c.second+i : c.second;
				if (ti < 0 || ti >= N || tj < 0 || tj >= N) continue;
				if (M[ti][tj]=='T' || (all[ti][tj].hd!=-1 && all[ti][tj].hd<=cost)) continue;
				all[ti][tj].hd = cost;
				q.push(make_pair(ti,tj));
				//cout << "add " << ti << "/" << tj << endl;
			}
		}
	}
	/*for (int i = 0; i < N; i++) {
		for (int j = 0; j < N; j++) {
			cout << all[i][j].hd << " ";
		}
		cout << endl;
	}*/
	int r = solve();
	cout << r << endl;
	//cout << work(2) << endl;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 336 KB Output is correct
2 Incorrect 1 ms 336 KB Output isn't correct
3 Correct 1 ms 336 KB Output is correct
4 Incorrect 1 ms 336 KB Output isn't correct
5 Correct 1 ms 592 KB Output is correct
6 Incorrect 1 ms 336 KB Output isn't correct
7 Execution timed out 1063 ms 13944 KB Time limit exceeded
8 Correct 1 ms 336 KB Output is correct
9 Correct 1 ms 336 KB Output is correct
10 Correct 1 ms 336 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Incorrect 1 ms 2384 KB Output isn't correct
13 Correct 1 ms 2552 KB Output is correct
14 Correct 2 ms 2384 KB Output is correct
15 Incorrect 1 ms 2384 KB Output isn't correct
16 Incorrect 1 ms 2384 KB Output isn't correct
17 Incorrect 1 ms 2384 KB Output isn't correct
18 Incorrect 1 ms 2384 KB Output isn't correct
19 Incorrect 1 ms 2384 KB Output isn't correct
20 Incorrect 1 ms 2552 KB Output isn't correct
21 Incorrect 1 ms 2384 KB Output isn't correct
22 Incorrect 1 ms 2384 KB Output isn't correct
23 Incorrect 1 ms 2384 KB Output isn't correct
24 Incorrect 1 ms 2384 KB Output isn't correct
25 Incorrect 1 ms 2384 KB Output isn't correct
26 Incorrect 1 ms 2384 KB Output isn't correct
27 Incorrect 1 ms 2396 KB Output isn't correct
28 Incorrect 2 ms 2384 KB Output isn't correct
29 Incorrect 1 ms 2384 KB Output isn't correct
30 Incorrect 1 ms 2384 KB Output isn't correct
31 Incorrect 1 ms 2384 KB Output isn't correct
32 Incorrect 1 ms 2384 KB Output isn't correct
33 Incorrect 6 ms 4944 KB Output isn't correct
34 Incorrect 6 ms 5112 KB Output isn't correct
35 Correct 430 ms 13452 KB Output is correct
36 Incorrect 7 ms 6736 KB Output isn't correct
37 Incorrect 7 ms 6888 KB Output isn't correct
38 Correct 601 ms 19944 KB Output is correct
39 Incorrect 8 ms 6992 KB Output isn't correct
40 Incorrect 8 ms 7196 KB Output isn't correct
41 Correct 951 ms 25616 KB Output is correct
42 Incorrect 9 ms 7248 KB Output isn't correct
43 Incorrect 9 ms 7404 KB Output isn't correct
44 Execution timed out 1064 ms 32676 KB Time limit exceeded
45 Incorrect 14 ms 9296 KB Output isn't correct
46 Incorrect 12 ms 9552 KB Output isn't correct
47 Execution timed out 1061 ms 43372 KB Time limit exceeded
48 Incorrect 12 ms 9552 KB Output isn't correct
49 Incorrect 12 ms 9704 KB Output isn't correct
50 Execution timed out 1050 ms 53592 KB Time limit exceeded
51 Incorrect 14 ms 9808 KB Output isn't correct
52 Incorrect 13 ms 9464 KB Output isn't correct
53 Execution timed out 1079 ms 65536 KB Time limit exceeded
54 Incorrect 16 ms 9808 KB Output isn't correct
55 Incorrect 16 ms 9808 KB Output isn't correct
56 Runtime error 681 ms 65536 KB Execution killed with signal 9
57 Incorrect 25 ms 11600 KB Output isn't correct
58 Incorrect 19 ms 12112 KB Output isn't correct
59 Runtime error 761 ms 65536 KB Execution killed with signal 9
60 Incorrect 22 ms 12112 KB Output isn't correct
61 Incorrect 21 ms 12280 KB Output isn't correct
62 Runtime error 231 ms 65536 KB Execution killed with signal 9
63 Correct 172 ms 11600 KB Output is correct
64 Correct 261 ms 13128 KB Output is correct
65 Correct 272 ms 12112 KB Output is correct
66 Correct 204 ms 11664 KB Output is correct
67 Correct 218 ms 12288 KB Output is correct
68 Correct 69 ms 12116 KB Output is correct
69 Correct 57 ms 12360 KB Output is correct
70 Correct 65 ms 12112 KB Output is correct
71 Correct 51 ms 12112 KB Output is correct
72 Correct 36 ms 11704 KB Output is correct
73 Correct 126 ms 12368 KB Output is correct
74 Correct 469 ms 24692 KB Output is correct
75 Correct 322 ms 12368 KB Output is correct
76 Correct 225 ms 12368 KB Output is correct
77 Correct 521 ms 12368 KB Output is correct
78 Correct 442 ms 12368 KB Output is correct
79 Correct 622 ms 46648 KB Output is correct
80 Correct 301 ms 12368 KB Output is correct
81 Correct 339 ms 12368 KB Output is correct
82 Correct 587 ms 12712 KB Output is correct
83 Correct 530 ms 12668 KB Output is correct
84 Correct 468 ms 29424 KB Output is correct
85 Correct 916 ms 12812 KB Output is correct
86 Correct 693 ms 12368 KB Output is correct
87 Execution timed out 1059 ms 13744 KB Time limit exceeded
88 Correct 972 ms 12708 KB Output is correct
89 Runtime error 235 ms 65536 KB Execution killed with signal 9
90 Execution timed out 1068 ms 14068 KB Time limit exceeded
91 Execution timed out 1051 ms 18628 KB Time limit exceeded
92 Execution timed out 1035 ms 13172 KB Time limit exceeded