oj.uz

Submission #1117918

# Submission time Handle Problem Language Result Execution time Memory
1117918 2024-11-24T10:01:07 Z whatthemomooofun1729 Tug of War (BOI15_tug) C++17
18 / 100
 442 ms 6776 KB 
#include <iostream>
#include <algorithm>
#include <utility>
#include <vector>
#include <stack>
#include <map>
#include <queue>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cstring>
#include <cmath>
#include <functional>
#include <cassert>
#include <iomanip>
#include <numeric>
#include <bitset>
#include <sstream>
#include <chrono>
#include <random>

#define ff first
#define ss second
#define PB push_back
#define sz(x) int(x.size())
#define rsz resize
#define fch(xxx, yyy) for (auto xxx : yyy) // abusive notation
#define all(x) (x).begin(),(x).end()
#define eps 1e-9

// more abusive notation (use at your own risk):
// #define int ll

using namespace std;
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using vi = vector<int>;
using vll = vector<ll>;

// debugging
void __print(int x) {std::cerr << x;}
void __print(ll x) {std::cerr << x;} /* remember to uncomment this when not using THE MACRO */
void __print(unsigned x) {std::cerr << x;}
void __print(ull x) {std::cerr << x;}
void __print(float x) {std::cerr << x;}
void __print(double x) {std::cerr << x;}
void __print(ld x) {std::cerr << x;}
void __print(char x) {std::cerr << '\'' << x << '\'';}
void __print(const char *x) {std::cerr << '\"' << x << '\"';}
void __print(const string& x) {std::cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V> void __print(const pair<T, V> &x) {std::cerr << '{'; __print(x.ff); std::cerr << ", "; __print(x.ss); std::cerr << '}';}
template<typename T> void __print(const T& x) {int f = 0; std::cerr << '{'; for (auto &i: x) std::cerr << (f++ ? ", " : ""), __print(i); std::cerr << "}";}
void _print() {std::cerr << "]\n";}
template <typename T, typename... V> void _print(T t, V... v) {__print(t); if (sizeof...(v)) std::cerr << ", "; _print(v...);}
void println() {std::cerr << ">--------------------<" << endl;}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

// templates
template <class T> bool ckmin(T &a, const T &b) {return b<a ? a = b, 1 : 0;}
template <class T> bool ckmax(T &a, const T &b) {return b>a ? a = b, 1 : 0;}
template <class T> using gr = greater<T>;
template <class T> using vc = vector<T>;
template <class T> using p_q = priority_queue<T>;
template <class T> using pqg = priority_queue<T, vc<T>, gr<T>>;
template <class T1, class T2> using pr = pair<T1, T2>;
mt19937_64 rng_ll(chrono::steady_clock::now().time_since_epoch().count());
int rng(int M) {return (int)(rng_ll()%M);} /*returns any random number in [0, M) */

// const variables
constexpr int INF = (int)2e9;
constexpr int MOD = 998244353;
constexpr long double EPS = (ld)1e-10, PI = 3.1415926535;
constexpr ll LL_INF = (ll)3e18;
constexpr int mod = (int)1e9 + 7;
constexpr ll inverse = 500000004LL; // inverse of 2 modulo 1e9 + 7

void setIO(const string& str) {// fast input/output
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (str.empty()) return;
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
}

const int MAXN = int(3e4) + 5;
const int MAXK = int(40 * MAXN) + 5;
int N, K;
vc<pii> adj[MAXN * 2];
map<pii, vi> mp;
int deg[MAXN * 2], cc[MAXN * 2], edges[MAXN * 2], siz[MAXN * 2];
pii parent[MAXN * 2];
bitset<MAXK> dp1, dp2; // DP values: use the index trick
vi d;
vc<pii> v;
int sum = 0;
int cycle_end, cycle_start, final_edge;

int solve() {
    //debug("solving");
    int D = sz(d);
    if (D == 0) {
        return abs(sum) <= K;
    }
    dp1[d[0] + 20 * N] = dp2[-d[0] + 20 * N] = true; // base cases
    for (int i = 1; i < D; ++i) {
        dp2 = (dp1 << d[i]) | (dp1 >> d[i]);
        swap(dp2, dp1);
    }
    for (int i = 0; i <= 40 * N; ++i) {
        int sba = i - 20 * N;
        if (dp1[i] && abs(sba + sum) <= K) { // testing to see if a solution exists
            return 1;
        }
    }
    return 0;
}

void dfs1(int u) {
    //debug(u);
    fch(to, adj[u]) {
        if (cc[to.ff] != -1) continue;
        cc[to.ff] = cc[u];
        siz[cc[u]]++;
        dfs1(to.ff);
    }
}

void conn_comp() {
    for (int i = 1; i <= 2 * N; ++i) {
        cc[i] = -1;
    }
    for (int i = 1; i <= 2 * N; ++i) {
        if (cc[i] == -1) {
            cc[i] = i;
            siz[i] = 1;
            dfs1(i);
        }
    }
}

bool dfs(int u, int par) {
    //debug(u, par);
    deg[u] = 0;
    fch(to, adj[u]) {
        if (to.ff == par) continue; // skipping edge to parent vertex
        if (deg[to.ff] == 0) {
            cycle_end = u;
            cycle_start = to.ff;
            final_edge = to.ss;
            return true;
        }
        parent[to.ff] = {u, to.ss};
        if (dfs(to.ff, parent[to.ff].ff))
            return true;
    }
    return false;
}

signed main() { // TIME YOURSELF !!!
    setIO("");
    cin >> N >> K;
    for (int i = 0; i < 2 * N; ++i) {
        int l, r, s;
        cin >> l >> r >> s;
        r += N;
        adj[l].PB({r, s});
        adj[r].PB({l, s});
        mp[{l, r}].PB(s);
        deg[l]++, deg[r]++;
        v.PB({l, r});
        parent[i+1] = {-1, -1}; // just setting all of the values in parent[i] to -1
    }
    conn_comp();
    for (int i = 0; i < sz(v); ++i) {
        edges[cc[v[i].ff]]++;
    }
    for (int i = 1; i <= 2 * N; ++i) {
        if (edges[cc[i]] < siz[cc[i]]) {
            cout << "NO";
            return 0;
        }
    }
    queue<int> q;
    for (int i = 1; i <= 2 * N; ++i) {
        if (sz(adj[i]) == 1) {
            q.push(i);
            deg[i] = -1;
        }
    }
    while (!q.empty()) {
        int u = q.front();
        q.pop();
        //debug(u);
        fch(to, adj[u]) {
            if (deg[to.ff] == -1) continue;
            sum += (u <= N ? -1 : 1) * to.ss;
            //debug((u <= N ? -1 : 1) * to.ss);
            deg[to.ff]--;
            if (deg[to.ff] == 1) q.push(to.ff);
        }
    }
    for (auto i = mp.begin(); i != mp.end(); i++) {
        if (sz(i->ss) == 2) {
            int A = (i->ss)[0], B = (i->ss)[1];
            d.PB(abs(-A + B));
            deg[(i->ff).ff] = deg[(i->ff).ss] = 0;
        }
    }
    for (int i = 1; i <= 2 * N; ++i) {
        if (deg[i] == 2) {
            int S = 0, bit = 0;
            deg[i] = 0;
            //debug(i);
            dfs(i, parent[i].ff);
            //debug(cycle_end, cycle_start);
            for (int u = cycle_end; u != cycle_start; u = parent[u].ff, bit ^= 1) {
                S += (bit == 0 ? -1 : 1) * parent[u].ss;
                if (u == cycle_start) break;
            }
            //debug(final_edge);
            S += (bit == 0 ? -1 : 1) * final_edge;
            d.PB(abs(S));
        }
    }
//    debug(sum);
//    debug(d);
    cout << (solve() == 1 ? "YES" : "NO");
    return 0;
}

// TLE -> TRY NOT USING DEFINE INT LONG LONG
// CE -> CHECK LINE 45
// 5000 * 5000 size matrices are kinda big (potential mle)
// Do something, start simpler

Compilation message

tug.cpp: In function 'void setIO(const string&)':
tug.cpp:89:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tug.cpp:90:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 3920 KB Output is correct
2 Correct 2 ms 3920 KB Output is correct
3 Correct 3 ms 3920 KB Output is correct
4 Correct 3 ms 3920 KB Output is correct
5 Correct 3 ms 3920 KB Output is correct
6 Correct 3 ms 3920 KB Output is correct
7 Correct 3 ms 4088 KB Output is correct
8 Correct 3 ms 3920 KB Output is correct
9 Correct 3 ms 3920 KB Output is correct
10 Correct 4 ms 4088 KB Output is correct
11 Correct 2 ms 3948 KB Output is correct
12 Correct 3 ms 3920 KB Output is correct
13 Correct 3 ms 3920 KB Output is correct
14 Correct 3 ms 3932 KB Output is correct
15 Correct 3 ms 3920 KB Output is correct
16 Correct 3 ms 3920 KB Output is correct
17 Correct 3 ms 3920 KB Output is correct
18 Correct 3 ms 3920 KB Output is correct
19 Correct 3 ms 3920 KB Output is correct
20 Correct 3 ms 3920 KB Output is correct
21 Correct 1 ms 3408 KB Output is correct
22 Correct 2 ms 3920 KB Output is correct
23 Correct 3 ms 3920 KB Output is correct
24 Correct 3 ms 3920 KB Output is correct
25 Correct 3 ms 3920 KB Output is correct

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 3920 KB Output is correct
2 Correct 2 ms 3920 KB Output is correct
3 Correct 3 ms 3920 KB Output is correct
4 Correct 3 ms 3920 KB Output is correct
5 Correct 3 ms 3920 KB Output is correct
6 Correct 3 ms 3920 KB Output is correct
7 Correct 3 ms 4088 KB Output is correct
8 Correct 3 ms 3920 KB Output is correct
9 Correct 3 ms 3920 KB Output is correct
10 Correct 4 ms 4088 KB Output is correct
11 Correct 2 ms 3948 KB Output is correct
12 Correct 3 ms 3920 KB Output is correct
13 Correct 3 ms 3920 KB Output is correct
14 Correct 3 ms 3932 KB Output is correct
15 Correct 3 ms 3920 KB Output is correct
16 Correct 3 ms 3920 KB Output is correct
17 Correct 3 ms 3920 KB Output is correct
18 Correct 3 ms 3920 KB Output is correct
19 Correct 3 ms 3920 KB Output is correct
20 Correct 3 ms 3920 KB Output is correct
21 Correct 1 ms 3408 KB Output is correct
22 Correct 2 ms 3920 KB Output is correct
23 Correct 3 ms 3920 KB Output is correct
24 Correct 3 ms 3920 KB Output is correct
25 Correct 3 ms 3920 KB Output is correct
26 Correct 132 ms 4388 KB Output is correct
27 Correct 23 ms 4432 KB Output is correct
28 Correct 129 ms 4176 KB Output is correct
29 Correct 21 ms 4432 KB Output is correct
30 Correct 143 ms 4404 KB Output is correct
31 Correct 21 ms 4432 KB Output is correct
32 Correct 149 ms 4180 KB Output is correct
33 Correct 22 ms 4432 KB Output is correct
34 Correct 13 ms 4600 KB Output is correct
35 Correct 21 ms 4432 KB Output is correct
36 Correct 131 ms 4176 KB Output is correct
37 Correct 25 ms 4432 KB Output is correct
38 Correct 137 ms 4176 KB Output is correct
39 Correct 22 ms 4432 KB Output is correct
40 Correct 137 ms 4176 KB Output is correct
41 Correct 22 ms 4600 KB Output is correct
42 Correct 131 ms 4176 KB Output is correct
43 Correct 29 ms 4432 KB Output is correct
44 Correct 130 ms 4176 KB Output is correct
45 Correct 21 ms 4432 KB Output is correct
46 Correct 128 ms 4176 KB Output is correct
47 Correct 4 ms 3920 KB Output is correct
48 Correct 71 ms 4520 KB Output is correct
49 Incorrect 69 ms 4432 KB Output isn't correct
50 Halted 0 ms 0 KB -

Subtask #3
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 415 ms 5836 KB Output is correct
2 Correct 14 ms 6348 KB Output is correct
3 Correct 423 ms 5856 KB Output is correct
4 Correct 15 ms 6348 KB Output is correct
5 Correct 412 ms 5836 KB Output is correct
6 Correct 14 ms 6348 KB Output is correct
7 Correct 405 ms 5836 KB Output is correct
8 Correct 14 ms 6348 KB Output is correct
9 Correct 428 ms 6004 KB Output is correct
10 Correct 14 ms 6348 KB Output is correct
11 Correct 417 ms 5836 KB Output is correct
12 Correct 14 ms 6348 KB Output is correct
13 Correct 396 ms 5968 KB Output is correct
14 Correct 409 ms 5836 KB Output is correct
15 Correct 13 ms 6348 KB Output is correct
16 Correct 442 ms 5836 KB Output is correct
17 Correct 14 ms 6348 KB Output is correct
18 Correct 421 ms 5848 KB Output is correct
19 Correct 16 ms 6348 KB Output is correct
20 Correct 435 ms 5852 KB Output is correct
21 Correct 13 ms 6092 KB Output is correct
22 Incorrect 214 ms 6776 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #4
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 3920 KB Output is correct
2 Correct 2 ms 3920 KB Output is correct
3 Correct 3 ms 3920 KB Output is correct
4 Correct 3 ms 3920 KB Output is correct
5 Correct 3 ms 3920 KB Output is correct
6 Correct 3 ms 3920 KB Output is correct
7 Correct 3 ms 4088 KB Output is correct
8 Correct 3 ms 3920 KB Output is correct
9 Correct 3 ms 3920 KB Output is correct
10 Correct 4 ms 4088 KB Output is correct
11 Correct 2 ms 3948 KB Output is correct
12 Correct 3 ms 3920 KB Output is correct
13 Correct 3 ms 3920 KB Output is correct
14 Correct 3 ms 3932 KB Output is correct
15 Correct 3 ms 3920 KB Output is correct
16 Correct 3 ms 3920 KB Output is correct
17 Correct 3 ms 3920 KB Output is correct
18 Correct 3 ms 3920 KB Output is correct
19 Correct 3 ms 3920 KB Output is correct
20 Correct 3 ms 3920 KB Output is correct
21 Correct 1 ms 3408 KB Output is correct
22 Correct 2 ms 3920 KB Output is correct
23 Correct 3 ms 3920 KB Output is correct
24 Correct 3 ms 3920 KB Output is correct
25 Correct 3 ms 3920 KB Output is correct
26 Correct 132 ms 4388 KB Output is correct
27 Correct 23 ms 4432 KB Output is correct
28 Correct 129 ms 4176 KB Output is correct
29 Correct 21 ms 4432 KB Output is correct
30 Correct 143 ms 4404 KB Output is correct
31 Correct 21 ms 4432 KB Output is correct
32 Correct 149 ms 4180 KB Output is correct
33 Correct 22 ms 4432 KB Output is correct
34 Correct 13 ms 4600 KB Output is correct
35 Correct 21 ms 4432 KB Output is correct
36 Correct 131 ms 4176 KB Output is correct
37 Correct 25 ms 4432 KB Output is correct
38 Correct 137 ms 4176 KB Output is correct
39 Correct 22 ms 4432 KB Output is correct
40 Correct 137 ms 4176 KB Output is correct
41 Correct 22 ms 4600 KB Output is correct
42 Correct 131 ms 4176 KB Output is correct
43 Correct 29 ms 4432 KB Output is correct
44 Correct 130 ms 4176 KB Output is correct
45 Correct 21 ms 4432 KB Output is correct
46 Correct 128 ms 4176 KB Output is correct
47 Correct 4 ms 3920 KB Output is correct
48 Correct 71 ms 4520 KB Output is correct
49 Incorrect 69 ms 4432 KB Output isn't correct
50 Halted 0 ms 0 KB -