Submission #335741

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
335741	2020-12-13T19:39:09 Z	12tqian	Tug of War (BOI15_tug)	C++17	23 / 100	213 ms	4972 KB

#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <iostream>
#include <iomanip>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <vector>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

typedef long long ll;
typedef long double ld;
typedef double db;
typedef string str;

typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<db, db> pd;

typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<ll> vl;
typedef vector<db> vd;
typedef vector<str> vs;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<pd> vpd;

#define mp make_pair
#define f first
#define s second
#define sz(x) (int) (x).size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define sor(x) sort(all(x))
#define rsz resize
#define resz resize
#define ins insert
#define ft front()
#define bk back()
#define pf push_front
#define pb push_back
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound

#define f1r(i, a, b) for(int i = (a); i < (b); ++i)
#define f0r(i, a) f1r(i, 0, a)
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i,0,a)
#define ROF(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define R0F(i, a) ROF(i, 0, a)
#define trav(a, x) for (auto& a : x)

mt19937 rng((uint32_t) chrono::steady_clock::now().time_since_epoch().count());

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 a < b ? a = b, 1 : 0; }
template<class T> using V = vector<T>;

#ifdef LOCAL
#define dbg(...) debug(#__VA_ARGS__, __VA_ARGS__);
#else
#define dbg(...) 17;
#endif

template<typename T, typename S> ostream& operator << (ostream &os, const pair<T, S> &p) { return os << "(" << p.first << ", " << p.second << ")"; }
template<typename C, typename T = decay<decltype(*begin(declval<C>()))>, typename enable_if<!is_same<C, string>::value>::type* = nullptr>
ostream& operator << (ostream &os, const C &c) { bool f = true; os << "{"; for (const auto &x : c) { if (!f) os << ", "; f = false; os << x; } return os << "}"; }
template<typename T> void debug(string s, T x) { cerr << s << " = " << x << "\n"; }
template<typename T, typename... Args> void debug(string s, T x, Args... args) { cerr << s.substr(0, s.find(',')) << " = " << x << " | "; debug(s.substr(s.find(',') + 2), args...); }

constexpr int pct(int x) { return __builtin_popcount(x); }
constexpr int bits(int x) { return 31 - __builtin_clz(x); } // floor(log2(x))

namespace input {
    template<class T> void re(complex<T>& x);
    template<class T1, class T2> void re(pair<T1, T2>& p);
    template<class T> void re(vector<T>& a);
    template<class T, int SZ> void re(array<T, SZ>& a);
    template<class T> void re(T& x) { cin >> x; }
    void re(double& x) { string t; re(t); x = stod(t); }
    void re(ld& x) { string t; re(t); x = stold(t); }
    template<class T, class... Ts> void re(T& t, Ts&... ts) {
        re(t); re(ts...); }
    template<class T> void re(complex<T>& x) { T a, b; re(a, b); x = cd(a, b); }
    template<class T1, class T2> void re(pair<T1, T2>& p) { re(p.f, p.s); }
    template<class T> void re(vector<T>& a) { F0R(i, sz(a)) re(a[i]); }
    template<class T, int SZ> void re(array<T, SZ>& a) { F0R(i, SZ) re(a[i]); }
}

using namespace input;

namespace output {
    void pr(int x) { cout << x; }
    void pr(long x) { cout << x; }
    void pr(ll x) { cout << x; }
    void pr(unsigned x) { cout << x; }
    void pr(unsigned long x) { cout << x; }
    void pr(unsigned long long x) { cout << x; }
    void pr(float x) { cout << x; }
    void pr(double x) { cout << x; }
    void pr(ld x) { cout << x; }
    void pr(char x) { cout << x; }
    void pr(const char* x) { cout << x; }
    void pr(const string& x) { cout << x; }
    void pr(bool x) { pr(x ? "true" : "false"); }
    template<class T> void pr(const complex<T>& x) { cout << x; }
    template<class T1, class T2> void pr(const pair<T1, T2>& x);
    template<class T> void pr(const T& x);
    template<class T, class... Ts> void pr(const T& t, const Ts&... ts) {
        pr(t); pr(ts...); }
    template<class T1, class T2> void pr(const pair<T1,T2>& x) {
        pr("{", x.f, ", ", x.s, "}"); }
    template<class T> void pr(const T& x) {
        pr("{"); // const iterator needed for vector<bool>
        bool fst = 1; for (const auto& a: x) pr(!fst ? ", " : "", a), fst = 0;
        pr("}"); }
    void ps() { pr("\n"); } // print w/ spaces
    template<class T, class... Ts> void ps(const T& t, const Ts&... ts) {
        pr(t); if (sizeof...(ts)) pr(" "); ps(ts...); }
    void pc() { pr("]\n"); } // debug w/ commas
    template<class T, class... Ts> void pc(const T& t, const Ts&... ts) {
        pr(t); if (sizeof...(ts)) pr(", "); pc(ts...); }
}

using namespace output;

namespace io {
    void setIn(string s) { freopen(s.c_str(), "r", stdin); }
    void setOut(string s) { freopen(s.c_str(), "w", stdout); }
    void setIO(string s = "") {
        cin.sync_with_stdio(0); cin.tie(0);
        if (sz(s)) { setIn(s + ".in"), setOut(s + ".out"); }
    }
}

using namespace io;

const int MOD = 1e9 + 7; // 998244353;
const ld PI = acos((ld) -1);

typedef std::decay <decltype(MOD)>::type mod_t;
struct mi {
    mod_t val;
    explicit operator mod_t() const { return val; }
    mi() { val = 0; }
    mi(const long long& v) {
        val = (-MOD <= v && v <= MOD) ? v : v % MOD;
        if (val < 0) val += MOD; }
    friend std::istream& operator >> (std::istream& in, mi& a) {
        long long x; std::cin >> x; a = mi(x); return in; }
    friend std::ostream& operator << (std::ostream& os, const mi& a) { return os << a.val; }
    friend bool operator == (const mi& a, const mi& b) { return a.val == b.val; }
    friend bool operator != (const mi& a, const mi& b) { return !(a == b); }
    friend bool operator < (const mi& a, const mi& b) { return a.val < b.val; }
    friend bool operator > (const mi& a, const mi& b) { return a.val > b.val; }
    friend bool operator <= (const mi& a, const mi& b) { return a.val <= b.val; }
    friend bool operator >= (const mi& a, const mi& b) { return a.val >= b.val; }
    mi operator - () const { return mi(-val); }
    mi& operator += (const mi& m) {
        if ((val += m.val) >= MOD) val -= MOD;
        return *this; }
    mi& operator -= (const mi& m) {
        if ((val -= m.val) < 0) val += MOD;
        return *this; }
    mi& operator *= (const mi& m) { val = (long long) val * m.val % MOD;
        return *this; }
    friend mi pow(mi a, long long p) {
        mi ans = 1; assert(p >= 0);
        for (; p; p /= 2, a *= a) if (p & 1) ans *= a;
        return ans; }
    friend mi inv(const mi& a) { assert(a != 0); return pow(a, MOD - 2); }
    mi& operator /= (const mi& m) { return (*this) *= inv(m); }
    friend mi operator + (mi a, const mi& b) { return a += b; }
    friend mi operator - (mi a, const mi& b) { return a -= b; }
    friend mi operator * (mi a, const mi& b) { return a *= b; }
    friend mi operator / (mi a, const mi& b) { return a /= b; }
};
typedef pair<mi, mi> pmi;
typedef vector<mi> vmi;
typedef vector<pmi> vpmi;

int main() {
    const int INF = 1e9;
    setIO("");

    int n, k; re(n, k);
    // right minus left
    auto no = []() {
        ps("NO");
        exit(0);
    };
    auto yes = []() {
        ps("YES");
        exit(0);
    };

    vector<multiset<pi>> adj(2 * n);
    f0r(i, 2 * n) {
        int u, v, w; re(u, v, w);
        u--, v--; v += n;
        adj[u].emplace(v, w);
        adj[v].emplace(u, -w);
    }

    multiset<pi> use;
    f0r(i, 2 * n) {
        if (sz(adj[i]) == 0) continue;
        use.emplace(sz(adj[i]), i);
    }

    auto one_rem = [&](int u, int v, int w) {
        assert(use.find({sz(adj[u]), u}) != use.end());
        use.erase(use.find({sz(adj[u]), u}));

        assert(adj[u].find({v, w}) != adj[u].end());
        adj[u].erase(adj[u].find({v, w}));
        if (sz(adj[u]) == 0) return;

        use.emplace(sz(adj[u]), u);
    };
    auto rem = [&](int u, int v, int w) {
        assert(u != v);
        one_rem(u, v, w);
        one_rem(v, u, -w);
    };

    int diff = 0;
    vector<int> vis(2 * n);
    // these are forced
    while (!use.empty()) {
        auto beg = *use.begin();
        if (beg.f > 1) break;

        int u = beg.s;
        int v = (*adj[u].begin()).f;
        int w = (*adj[u].begin()).s;

        // you delete the reverse edge also
        rem(u, v, w);

        vis[u] = 1;
        diff += -w;
    }

    vi can;

    f0r(i, 2 * n) {
        if (vis[i]) continue;
        if (sz(adj[i]) == 0) continue;
        int val = 0;
        int u = i;
        int v, w;

        for (auto nxt : adj[u]) {
            if (vis[nxt.f] == 0) {
                v = nxt.f;
                w = nxt.s;
                break;
            }
        }
        assert(adj[u].find({v, w}) != adj[u].end());
        assert(adj[v].find({u, -w}) != adj[v].end());
        adj[u].erase(adj[u].find({v, w}));
        adj[v].erase(adj[v].find({u, -w}));
        // u to v weight w

        val += w;

        function<void(int)> dfs = [&](int src) {
            vis[src] = 1;

            for (auto nxt : adj[src]) {
                int go = nxt.f;
                int we = nxt.s;

                if (vis[go]) {
                    continue;
                } else { 
                    val += we;
                    dfs(go);
                }

            }
        };

        dfs(v);

        val = abs(val);
        can.eb(val);
    }
    int res = 0;
    f0r(i, 2 * n) res += vis[i];
    if (res != 2 * n) no();

    // sum stuff in can, add to diff, abs between -k, k
    // you want to make a sum in the range of left, right
    const int MX = 1e6 + 5;
    const int ADD = MX / 2;

    bitset<MX> B;

    f0r(i, sz(can)) {
        int x = can[i];

        if (i == 0) { 
            B[x + ADD] = 1;
            B[-x + ADD] = 1;
            continue;
        }
        B <<= x;
        B |= (B >> (2 * x));
    }

    f1r(i, -k - diff, k + diff + 1) {
        int x = i+ADD;
        if (B[x]) {
            yes();
        }
    }

    no();    
    return 0;
}

Compilation message

tug.cpp: In function 'int main()':
tug.cpp:208:15: warning: unused variable 'INF' [-Wunused-variable]
  208 |     const int INF = 1e9;
      |               ^~~
tug.cpp: In function 'void io::setIn(std::string)':
tug.cpp:153:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  153 |     void setIn(string s) { freopen(s.c_str(), "r", stdin); }
      |                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
tug.cpp: In function 'void io::setOut(std::string)':
tug.cpp:154:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  154 |     void setOut(string s) { freopen(s.c_str(), "w", stdout); }
      |                             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
tug.cpp: In function 'int main()':
tug.cpp:287:32: warning: 'w' may be used uninitialized in this function [-Wmaybe-uninitialized]
  287 |         assert(adj[v].find({u, -w}) != adj[v].end());
      |                                ^

Subtask #1
0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	748 KB	Output is correct
2	Correct	1 ms	748 KB	Output is correct
3	Correct	1 ms	748 KB	Output is correct
4	Correct	1 ms	748 KB	Output is correct
5	Correct	1 ms	748 KB	Output is correct
6	Correct	1 ms	748 KB	Output is correct
7	Correct	1 ms	748 KB	Output is correct
8	Correct	1 ms	748 KB	Output is correct
9	Correct	1 ms	748 KB	Output is correct
10	Correct	1 ms	748 KB	Output is correct
11	Correct	2 ms	748 KB	Output is correct
12	Correct	1 ms	748 KB	Output is correct
13	Correct	2 ms	748 KB	Output is correct
14	Correct	1 ms	748 KB	Output is correct
15	Correct	1 ms	748 KB	Output is correct
16	Correct	1 ms	748 KB	Output is correct
17	Correct	1 ms	748 KB	Output is correct
18	Correct	1 ms	748 KB	Output is correct
19	Correct	1 ms	748 KB	Output is correct
20	Correct	1 ms	748 KB	Output is correct
21	Correct	1 ms	364 KB	Output is correct
22	Correct	1 ms	748 KB	Output is correct
23	Incorrect	1 ms	748 KB	Output isn't correct
24	Halted	0 ms	0 KB	-

Subtask #2
0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	748 KB	Output is correct
2	Correct	1 ms	748 KB	Output is correct
3	Correct	1 ms	748 KB	Output is correct
4	Correct	1 ms	748 KB	Output is correct
5	Correct	1 ms	748 KB	Output is correct
6	Correct	1 ms	748 KB	Output is correct
7	Correct	1 ms	748 KB	Output is correct
8	Correct	1 ms	748 KB	Output is correct
9	Correct	1 ms	748 KB	Output is correct
10	Correct	1 ms	748 KB	Output is correct
11	Correct	2 ms	748 KB	Output is correct
12	Correct	1 ms	748 KB	Output is correct
13	Correct	2 ms	748 KB	Output is correct
14	Correct	1 ms	748 KB	Output is correct
15	Correct	1 ms	748 KB	Output is correct
16	Correct	1 ms	748 KB	Output is correct
17	Correct	1 ms	748 KB	Output is correct
18	Correct	1 ms	748 KB	Output is correct
19	Correct	1 ms	748 KB	Output is correct
20	Correct	1 ms	748 KB	Output is correct
21	Correct	1 ms	364 KB	Output is correct
22	Correct	1 ms	748 KB	Output is correct
23	Incorrect	1 ms	748 KB	Output isn't correct
24	Halted	0 ms	0 KB	-

Subtask #3
23.0 / 23.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	197 ms	4700 KB	Output is correct
2	Correct	21 ms	4204 KB	Output is correct
3	Correct	201 ms	4972 KB	Output is correct
4	Correct	22 ms	4440 KB	Output is correct
5	Correct	197 ms	4972 KB	Output is correct
6	Correct	21 ms	4332 KB	Output is correct
7	Correct	197 ms	4844 KB	Output is correct
8	Correct	21 ms	4332 KB	Output is correct
9	Correct	207 ms	4844 KB	Output is correct
10	Correct	20 ms	4332 KB	Output is correct
11	Correct	200 ms	4972 KB	Output is correct
12	Correct	21 ms	4332 KB	Output is correct
13	Correct	198 ms	4972 KB	Output is correct
14	Correct	198 ms	4844 KB	Output is correct
15	Correct	21 ms	4332 KB	Output is correct
16	Correct	196 ms	4844 KB	Output is correct
17	Correct	21 ms	4332 KB	Output is correct
18	Correct	213 ms	4844 KB	Output is correct
19	Correct	23 ms	4332 KB	Output is correct
20	Correct	197 ms	4972 KB	Output is correct
21	Correct	29 ms	4460 KB	Output is correct
22	Correct	113 ms	4880 KB	Output is correct

Subtask #4
0 / 29.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	748 KB	Output is correct
2	Correct	1 ms	748 KB	Output is correct
3	Correct	1 ms	748 KB	Output is correct
4	Correct	1 ms	748 KB	Output is correct
5	Correct	1 ms	748 KB	Output is correct
6	Correct	1 ms	748 KB	Output is correct
7	Correct	1 ms	748 KB	Output is correct
8	Correct	1 ms	748 KB	Output is correct
9	Correct	1 ms	748 KB	Output is correct
10	Correct	1 ms	748 KB	Output is correct
11	Correct	2 ms	748 KB	Output is correct
12	Correct	1 ms	748 KB	Output is correct
13	Correct	2 ms	748 KB	Output is correct
14	Correct	1 ms	748 KB	Output is correct
15	Correct	1 ms	748 KB	Output is correct
16	Correct	1 ms	748 KB	Output is correct
17	Correct	1 ms	748 KB	Output is correct
18	Correct	1 ms	748 KB	Output is correct
19	Correct	1 ms	748 KB	Output is correct
20	Correct	1 ms	748 KB	Output is correct
21	Correct	1 ms	364 KB	Output is correct
22	Correct	1 ms	748 KB	Output is correct
23	Incorrect	1 ms	748 KB	Output isn't correct
24	Halted	0 ms	0 KB	-

Submission #335741

Compilation message

Subtask #1 0 / 18.0

Subtask #2 0 / 30.0

Subtask #3 23.0 / 23.0

Subtask #4 0 / 29.0

Subtask #1
0 / 18.0

Subtask #2
0 / 30.0

Subtask #3
23.0 / 23.0

Subtask #4
0 / 29.0