oj.uz

Submission #337745

# Submission time Handle Problem Language Result Execution time Memory
337745 2020-12-21T13:29:31 Z HynDuf Tug of War (BOI15_tug) C++11
23 / 100
 173 ms 8044 KB 
#include <bits/stdc++.h>
#define F first
#define S second
#define eb emplace_back
#define pb push_back
#define pf push_front
#define all(v) (v).begin(), (v).end()
#define rep(i, l, r) for (int i = (l); i <= (r); i++)
#define Rep(i, r, l) for (int i = (r); i >= (l); i--)
#define DB(X) {cerr << #X << " = " << X << '\n';}
#define DB1(A, _) {cerr << #A << "[" << _ << "] = " << A[_] << '\n';}
#define DB2(A, _, __) {cerr << #A << "[" << _ << "][" << __ << "] = " << A[_][__] << '\n';}
#define DB3(A, _, __, ____) {cerr << #A << "[" << _ << "][" << __ << "][" << ___ << "] = " << A[_][__][___] << '\n';}
#define PR(A, l, r) {cerr << '\n'; rep(_, l, r) DB1(A, _); cerr << '\n';}
#define left ___left
#define right ___right
#define next ___next
#define prev ___prev
#define y1 ___y1
#define y0 ___y0
#define j0 ___j0
#define SZ(x) ((int)(x).size())
using ll = long long;
using ld = long double;
using namespace std;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef vector<ii> vii;
typedef vector<ll> vl;
const int N = 6e4 + 2, NN = 600002;
int n, cnt[N], K;
struct Tug
{
    int l, r, s;
} tug[N];
set<int> tu[N];
vii g[N];
vi obj;
bool vis[N];
int cur;
void dfs(int u, int r)
{
    for (const ii &v : g[u]) if (!vis[v.S])
    {
        vis[v.S] = 1;
        if (u > n) cur -= tug[v.S].s;
        else cur += tug[v.S].s;
        if (v.F != r) dfs(v.F, r);
    }
}
bitset<NN> dp;
int main()
{
//    freopen("T.in", "r", stdin);
//    freopen("T.out", "w", stdout);
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    cin >> n >> K;
    rep(i, 1, n << 1)
    {
        int l, r, s;
        cin >> l >> r >> s;
        r += n;
        tug[i] = {l, r, s};
        cnt[l]++, cnt[r]++;
        tu[l].insert(i);
        tu[r].insert(i);
    }
    queue<int> q;
    rep(i, 1, (n << 1)) if (cnt[i] == 0)
    {
        cout << "NO";
        return 0;
    } else if (cnt[i] == 1) q.push(i);
    int ans = 0;
    while (!q.empty())
    {
        int u = q.front();
        q.pop();
        if (cnt[u] == 0)
        {
            cout << "NO";
            return 0;
        }
        assert(cnt[u] == 1);
        assert(SZ(tu[u]) == 1);
        cnt[u] = 0;
        int id = *tu[u].begin();
        int ano = (tug[id].l == u ? tug[id].r : tug[id].l);
        if (--cnt[ano] == 1) q.push(ano);
        if (u > n) ans -= tug[id].s;
        else ans += tug[id].s;
        tu[ano].erase(id);
    }
    rep(u, 1, (n << 1)) if (cnt[u])
    {
        assert(cnt[u] == 2);
        assert(SZ(tu[u]) == 2);
        auto it = tu[u].begin();
        int ano = (tug[*it].l == u ? tug[*it].r : tug[*it].l);
        g[u].eb(ano, *it);
        it++;
        ano = (tug[*it].l == u ? tug[*it].r : tug[*it].l);
        g[u].eb(ano, *it);
    }
    rep(i, 1, (n << 1)) if (cnt[i] == 2 && !vis[i])
    {
        cur = 0;
        dfs(i, i);
        obj.eb(abs(cur));
    }
    obj.eb(abs(ans));
    dp[0] = 1;
    int tot = 0;
    for (int v : obj) dp |= dp << v, tot += v;
    rep(i, 0, tot) if (dp[i] && abs(tot - i - i) <= K)
    {
        cout << "YES";
        return 0;
    }
    cout << "NO";
    return 0;
}

Subtask #1
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 4844 KB Output is correct
2 Correct 4 ms 4844 KB Output is correct
3 Incorrect 4 ms 4844 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 4844 KB Output is correct
2 Correct 4 ms 4844 KB Output is correct
3 Incorrect 4 ms 4844 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 172 ms 7916 KB Output is correct
2 Correct 16 ms 7040 KB Output is correct
3 Correct 172 ms 8044 KB Output is correct
4 Correct 15 ms 7020 KB Output is correct
5 Correct 168 ms 8044 KB Output is correct
6 Correct 15 ms 7040 KB Output is correct
7 Correct 166 ms 8020 KB Output is correct
8 Correct 15 ms 7020 KB Output is correct
9 Correct 173 ms 7916 KB Output is correct
10 Correct 15 ms 7020 KB Output is correct
11 Correct 167 ms 7916 KB Output is correct
12 Correct 14 ms 7020 KB Output is correct
13 Correct 168 ms 7916 KB Output is correct
14 Correct 168 ms 8044 KB Output is correct
15 Correct 15 ms 7040 KB Output is correct
16 Correct 168 ms 8044 KB Output is correct
17 Correct 15 ms 7020 KB Output is correct
18 Correct 170 ms 8020 KB Output is correct
19 Correct 15 ms 7020 KB Output is correct
20 Correct 167 ms 7916 KB Output is correct
21 Correct 16 ms 7020 KB Output is correct
22 Correct 128 ms 7424 KB Output is correct

Subtask #4
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 4844 KB Output is correct
2 Correct 4 ms 4844 KB Output is correct
3 Incorrect 4 ms 4844 KB Output isn't correct
4 Halted 0 ms 0 KB -