oj.uz

Submission #681955

# Submission time Handle Problem Language Result Execution time Memory
681955 2023-01-14T23:40:30 Z MilosMilutinovic Tug of War (BOI15_tug) C++14
23 / 100
 427 ms 5844 KB 
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <queue>
#include <ctime>
#include <cassert>
#include <complex>
#include <string>
#include <cstring>
#include <chrono>
#include <random>
#include <bitset>
#include <array>
using namespace std;

typedef long long ll;

const int N = 30333;
int n, k;
int l[2 * N];
int r[2 * N];
int s[2 * N];
vector<int> g[4 * N];
int ver;
int pos;
bool was[4 * N];
ll sum[2];
vector<int> comp;
bool have[4 * N];
bool taken[4 * N];

void addEdge(int v, int u) {
	g[v].push_back(u);
	g[u].push_back(v);
}

void dfs(int v) {
	if (v < 2 * n) {
		sum[ver & 1] += s[v];
		ver++;
	} else pos++;
	was[v] = true;
	comp.push_back(v);
	for (int u : g[v])
		if (!was[u])
			dfs(u);
}

bool OK;
void Go(int p) {
	taken[p] = true;
	for (int x : g[p]) {
		if (!have[x]) {
			int w = (p ^ (2 * n + l[x]) ^ (3 * n + r[x]));
			if (taken[w])
				OK = false;
			else {
				sum[(w < 3 * n)] += s[x];
				taken[w] = true;
				have[x] = true;
				Go(w);
			}
		}
	}
}

bool Try(int i, int p) {
	OK = true;
	for (int it : comp) {
		have[it] = false;
		taken[it] = false;
	}
	sum[0] = 0;
	sum[1] = 0;
	sum[(p < 3 * n)] += s[i];
	have[i] = true;
	Go(p);
	return OK;
}

int main()
{
//	freopen("input.txt", "r", stdin);
//	freopen("output.txt", "w", stdout);

	scanf("%d%d", &n, &k);
	assert(k >= 0);
	for (int i = 0; i < 2 * n; i++) {
		scanf("%d%d%d", &l[i], &r[i], &s[i]);
		--l[i];--r[i];
		addEdge(i, 2 * n + l[i]);
		addEdge(i, 3 * n + r[i]);
	}
	vector<int> canSame, mustDiff;
	for (int i = 0; i < 2 * n; i++) if (!was[i]) {
		ver = 0;
		pos = 0;
		sum[0] = 0;
		sum[1] = 0;
		comp.clear();
		dfs(i);
		if (ver > pos) {
			printf("NO\n");
			return 0;
		}
		assert(Try(i, 3 * n + r[i]) || Try(i, 2 * n + l[i]));
		if (!Try(i, 3 * n + r[i])) {
			assert(Try(i, 2 * n + l[i]));
			mustDiff.push_back(sum[0] - sum[1]);
		}
		else if (!Try(i, 2 * n + l[i])) {
			assert(Try(i, 3 * n + r[i]));
			mustDiff.push_back(sum[0] - sum[1]);
		}
		else canSame.push_back(sum[0] - sum[1]);
	}
	bitset<40 * N + 1> dp;
	dp[20 * N] = 1;
	for (int x : canSame) {
		x = abs(x);
		dp = ((dp >> x) | (dp << x));
	}
	for (int x : mustDiff) {
		if (x < 0)
			dp = (dp >> (-x));
		else
			dp = (dp << x);
	}
	bool ok = false;
	for (int i = 0; i <= k; i++)
		if (dp[20 * N + i] || dp[20 * N - i])
			ok = true;
	if (ok || true)
		printf("YES\n");
	else
		printf("NO\n");

	return 0;
}

Compilation message

tug.cpp: In function 'int main()':
tug.cpp:93:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |  scanf("%d%d", &n, &k);
      |  ~~~~~^~~~~~~~~~~~~~~~
tug.cpp:96:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   96 |   scanf("%d%d%d", &l[i], &r[i], &s[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 18.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 3668 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 3668 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 427 ms 5476 KB Output is correct
2 Correct 10 ms 5236 KB Output is correct
3 Correct 413 ms 5456 KB Output is correct
4 Correct 11 ms 5204 KB Output is correct
5 Correct 397 ms 5460 KB Output is correct
6 Correct 11 ms 5204 KB Output is correct
7 Correct 349 ms 5456 KB Output is correct
8 Correct 10 ms 5216 KB Output is correct
9 Correct 384 ms 5460 KB Output is correct
10 Correct 11 ms 5204 KB Output is correct
11 Correct 359 ms 5460 KB Output is correct
12 Correct 10 ms 5204 KB Output is correct
13 Correct 349 ms 5456 KB Output is correct
14 Correct 362 ms 5460 KB Output is correct
15 Correct 10 ms 5204 KB Output is correct
16 Correct 356 ms 5424 KB Output is correct
17 Correct 10 ms 5204 KB Output is correct
18 Correct 394 ms 5472 KB Output is correct
19 Correct 13 ms 5204 KB Output is correct
20 Correct 353 ms 5568 KB Output is correct
21 Correct 15 ms 5844 KB Output is correct
22 Correct 239 ms 5400 KB Output is correct

Subtask #4
0 / 29.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 3668 KB Output isn't correct
2 Halted 0 ms 0 KB -