oj.uz

Submission #120067

# Submission time Handle Problem Language Result Execution time Memory
120067 2019-06-23T07:26:49 Z E869120 Tug of War (BOI15_tug) C++14
23 / 100
 665 ms 8440 KB 
#include <iostream>
#include <vector>
#include <queue>
#include <set>
#include <bitset>
using namespace std;
#pragma warning (disable: 4996)

bitset<1200001>F, H, I;

bool solve(int N, int K, vector<int>G) {
	F.set(0);
	for (int i = 0; i < G.size(); i++) {
		H = F; F = I;
		F |= (H << (G[i] * 2));
	}
	int sm = 0; for (int i = 0; i < G.size(); i++) sm += G[i];
	for (int i = sm - K; i <= sm + K; i++) {
		if (i >= 0 && i <= sm * 2 && F[i] == 1) return true;
	}
	return false;
}

set<pair<int, int>> G[60009];
int N, K, V1, V2, A[60009], B[60009], S[60009]; bool used[60009], colored[60009];
vector<pair<int, int>> X[60009];

int main() {
	scanf("%d%d", &N, &K);
	for (int i = 1; i <= N * 2; i++) {
		scanf("%d%d%d", &A[i], &B[i], &S[i]);
		G[A[i]].insert(make_pair(B[i] + N, i));
		G[B[i] + N].insert(make_pair(A[i], i));
	}

	queue<int>Q;
	for (int i = 1; i <= 2 * N; i++) {
		if (G[i].size() == 1) Q.push(i);
	}
	while (!Q.empty()) {
		int pos = Q.front(); Q.pop();
		auto itr = G[pos].begin();
		pair<int, int> E = (*itr);

		if (pos <= N) V1 += S[E.second];
		else V2 += S[E.second];

		used[E.second] = false; colored[pos] = true;
		G[pos].erase(make_pair(E.first, E.second));
		G[E.first].erase(make_pair(pos, E.second)); if (G[E.first].size() == 1) Q.push(E.first);
	}
	for (int i = 1; i <= 2 * N; i++) {
		if (colored[i] == false && G[i].size() == 0) {
			cout << "NO" << endl;
			return 0;
		}
	}
	for (int i = 1; i <= 2 * N; i++) {
		auto itr = G[i].begin();
		while (itr != G[i].end()) {
			X[i].push_back(*itr);
			itr++;
		}
	}

	vector<int>Z; Z.push_back(abs(V1 - V2));
	for (int i = 1; i <= 2 * N; i++) {
		if (colored[i] == true) continue;

		vector<int>E;
		if (X[i][0].first == X[i][1].first) {
			colored[i] = true; colored[X[i][0].first] = true;
			E.push_back(S[X[i][0].second]);
			E.push_back(S[X[i][1].second]);
		}
		else {
			int cx = i;
			while (true) {
				int nex = -1, cost = -1;
				for (int j = 0; j < X[cx].size(); j++) {
					if (colored[X[cx][j].first] == false) { nex = X[cx][j].first; cost = S[X[cx][j].second]; }
				}
				if (nex == -1) break;
				cx = nex; colored[cx] = true; E.push_back(cost);
			}
		}

		int pa = 0, pb = 0;
		for (int j = 0; j < E.size(); j++) { if (j % 2 == 0) pa += E[j]; else pb += E[j]; }
		Z.push_back(abs(pa - pb));
	}

	bool FinalAns = solve(N, K, Z);
	if (FinalAns == true) cout << "YES" << endl;
	else cout << "NO" << endl;
	return 0;
}

Compilation message

tug.cpp:7:0: warning: ignoring #pragma warning  [-Wunknown-pragmas]
 #pragma warning (disable: 4996)
 
tug.cpp: In function 'bool solve(int, int, std::vector<int>)':
tug.cpp:13:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < G.size(); i++) {
                  ~~^~~~~~~~~~
tug.cpp:17:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  int sm = 0; for (int i = 0; i < G.size(); i++) sm += G[i];
                              ~~^~~~~~~~~~
tug.cpp: In function 'int main()':
tug.cpp:80:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int j = 0; j < X[cx].size(); j++) {
                     ~~^~~~~~~~~~~~~~
tug.cpp:89:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int j = 0; j < E.size(); j++) { if (j % 2 == 0) pa += E[j]; else pb += E[j]; }
                   ~~^~~~~~~~~~
tug.cpp:29:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &N, &K);
  ~~~~~^~~~~~~~~~~~~~~~
tug.cpp:31:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d", &A[i], &B[i], &S[i]);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 5120 KB Output is correct
2 Incorrect 6 ms 5120 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 5120 KB Output is correct
2 Incorrect 6 ms 5120 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 622 ms 8272 KB Output is correct
2 Correct 23 ms 6912 KB Output is correct
3 Correct 665 ms 8388 KB Output is correct
4 Correct 22 ms 6912 KB Output is correct
5 Correct 635 ms 8312 KB Output is correct
6 Correct 26 ms 7040 KB Output is correct
7 Correct 649 ms 8344 KB Output is correct
8 Correct 21 ms 7040 KB Output is correct
9 Correct 620 ms 8312 KB Output is correct
10 Correct 24 ms 7040 KB Output is correct
11 Correct 661 ms 8284 KB Output is correct
12 Correct 22 ms 7032 KB Output is correct
13 Correct 651 ms 8440 KB Output is correct
14 Correct 628 ms 8316 KB Output is correct
15 Correct 20 ms 7040 KB Output is correct
16 Correct 627 ms 8276 KB Output is correct
17 Correct 20 ms 6912 KB Output is correct
18 Correct 605 ms 8320 KB Output is correct
19 Correct 20 ms 6912 KB Output is correct
20 Correct 629 ms 8280 KB Output is correct
21 Correct 22 ms 6912 KB Output is correct
22 Correct 311 ms 7552 KB Output is correct

Subtask #4
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 5120 KB Output is correct
2 Incorrect 6 ms 5120 KB Output isn't correct
3 Halted 0 ms 0 KB -