oj.uz

Submission #335742

# Submission time Handle Problem Language Result Execution time Memory
335742 2020-12-13T19:39:52 Z 12tqian Tug of War (BOI15_tug) C++17
100 / 100
 1538 ms 13568 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
18.0 / 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 2 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 2 ms 748 KB Output is correct
8 Correct 1 ms 748 KB Output is correct
9 Correct 2 ms 748 KB Output is correct
10 Correct 1 ms 748 KB Output is correct
11 Correct 1 ms 748 KB Output is correct
12 Correct 1 ms 748 KB Output is correct
13 Correct 1 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 0 ms 364 KB Output is correct
22 Correct 1 ms 748 KB Output is correct
23 Correct 1 ms 748 KB Output is correct
24 Correct 1 ms 748 KB Output is correct
25 Correct 1 ms 748 KB Output is correct

Subtask #2
30.0 / 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 2 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 2 ms 748 KB Output is correct
8 Correct 1 ms 748 KB Output is correct
9 Correct 2 ms 748 KB Output is correct
10 Correct 1 ms 748 KB Output is correct
11 Correct 1 ms 748 KB Output is correct
12 Correct 1 ms 748 KB Output is correct
13 Correct 1 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 0 ms 364 KB Output is correct
22 Correct 1 ms 748 KB Output is correct
23 Correct 1 ms 748 KB Output is correct
24 Correct 1 ms 748 KB Output is correct
25 Correct 1 ms 748 KB Output is correct
26 Correct 97 ms 1516 KB Output is correct
27 Correct 14 ms 1516 KB Output is correct
28 Correct 100 ms 1516 KB Output is correct
29 Correct 14 ms 1516 KB Output is correct
30 Correct 116 ms 1644 KB Output is correct
31 Correct 14 ms 1516 KB Output is correct
32 Correct 98 ms 1516 KB Output is correct
33 Correct 15 ms 1516 KB Output is correct
34 Correct 9 ms 1664 KB Output is correct
35 Correct 14 ms 1516 KB Output is correct
36 Correct 102 ms 1644 KB Output is correct
37 Correct 14 ms 1516 KB Output is correct
38 Correct 98 ms 1516 KB Output is correct
39 Correct 14 ms 1516 KB Output is correct
40 Correct 98 ms 1644 KB Output is correct
41 Correct 14 ms 1516 KB Output is correct
42 Correct 98 ms 1644 KB Output is correct
43 Correct 14 ms 1644 KB Output is correct
44 Correct 97 ms 1516 KB Output is correct
45 Correct 14 ms 1516 KB Output is correct
46 Correct 98 ms 1516 KB Output is correct
47 Correct 4 ms 1132 KB Output is correct
48 Correct 54 ms 1516 KB Output is correct
49 Correct 54 ms 1696 KB Output is correct
50 Correct 101 ms 1644 KB Output is correct
51 Correct 101 ms 1516 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 198 ms 4588 KB Output is correct
2 Correct 21 ms 4204 KB Output is correct
3 Correct 219 ms 4588 KB Output is correct
4 Correct 23 ms 4352 KB Output is correct
5 Correct 199 ms 4588 KB Output is correct
6 Correct 21 ms 4204 KB Output is correct
7 Correct 198 ms 4588 KB Output is correct
8 Correct 22 ms 4204 KB Output is correct
9 Correct 200 ms 4748 KB Output is correct
10 Correct 21 ms 4204 KB Output is correct
11 Correct 197 ms 4588 KB Output is correct
12 Correct 21 ms 4204 KB Output is correct
13 Correct 200 ms 4716 KB Output is correct
14 Correct 198 ms 4716 KB Output is correct
15 Correct 22 ms 4204 KB Output is correct
16 Correct 205 ms 4588 KB Output is correct
17 Correct 20 ms 4204 KB Output is correct
18 Correct 213 ms 4588 KB Output is correct
19 Correct 29 ms 4204 KB Output is correct
20 Correct 198 ms 4748 KB Output is correct
21 Correct 20 ms 4332 KB Output is correct
22 Correct 112 ms 4588 KB Output is correct

Subtask #4
29.0 / 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 2 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 2 ms 748 KB Output is correct
8 Correct 1 ms 748 KB Output is correct
9 Correct 2 ms 748 KB Output is correct
10 Correct 1 ms 748 KB Output is correct
11 Correct 1 ms 748 KB Output is correct
12 Correct 1 ms 748 KB Output is correct
13 Correct 1 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 0 ms 364 KB Output is correct
22 Correct 1 ms 748 KB Output is correct
23 Correct 1 ms 748 KB Output is correct
24 Correct 1 ms 748 KB Output is correct
25 Correct 1 ms 748 KB Output is correct
26 Correct 97 ms 1516 KB Output is correct
27 Correct 14 ms 1516 KB Output is correct
28 Correct 100 ms 1516 KB Output is correct
29 Correct 14 ms 1516 KB Output is correct
30 Correct 116 ms 1644 KB Output is correct
31 Correct 14 ms 1516 KB Output is correct
32 Correct 98 ms 1516 KB Output is correct
33 Correct 15 ms 1516 KB Output is correct
34 Correct 9 ms 1664 KB Output is correct
35 Correct 14 ms 1516 KB Output is correct
36 Correct 102 ms 1644 KB Output is correct
37 Correct 14 ms 1516 KB Output is correct
38 Correct 98 ms 1516 KB Output is correct
39 Correct 14 ms 1516 KB Output is correct
40 Correct 98 ms 1644 KB Output is correct
41 Correct 14 ms 1516 KB Output is correct
42 Correct 98 ms 1644 KB Output is correct
43 Correct 14 ms 1644 KB Output is correct
44 Correct 97 ms 1516 KB Output is correct
45 Correct 14 ms 1516 KB Output is correct
46 Correct 98 ms 1516 KB Output is correct
47 Correct 4 ms 1132 KB Output is correct
48 Correct 54 ms 1516 KB Output is correct
49 Correct 54 ms 1696 KB Output is correct
50 Correct 101 ms 1644 KB Output is correct
51 Correct 101 ms 1516 KB Output is correct
52 Correct 198 ms 4588 KB Output is correct
53 Correct 21 ms 4204 KB Output is correct
54 Correct 219 ms 4588 KB Output is correct
55 Correct 23 ms 4352 KB Output is correct
56 Correct 199 ms 4588 KB Output is correct
57 Correct 21 ms 4204 KB Output is correct
58 Correct 198 ms 4588 KB Output is correct
59 Correct 22 ms 4204 KB Output is correct
60 Correct 200 ms 4748 KB Output is correct
61 Correct 21 ms 4204 KB Output is correct
62 Correct 197 ms 4588 KB Output is correct
63 Correct 21 ms 4204 KB Output is correct
64 Correct 200 ms 4716 KB Output is correct
65 Correct 198 ms 4716 KB Output is correct
66 Correct 22 ms 4204 KB Output is correct
67 Correct 205 ms 4588 KB Output is correct
68 Correct 20 ms 4204 KB Output is correct
69 Correct 213 ms 4588 KB Output is correct
70 Correct 29 ms 4204 KB Output is correct
71 Correct 198 ms 4748 KB Output is correct
72 Correct 20 ms 4332 KB Output is correct
73 Correct 112 ms 4588 KB Output is correct
74 Correct 1522 ms 13420 KB Output is correct
75 Correct 114 ms 13164 KB Output is correct
76 Correct 1500 ms 13348 KB Output is correct
77 Correct 105 ms 13164 KB Output is correct
78 Correct 1477 ms 13292 KB Output is correct
79 Correct 1531 ms 13348 KB Output is correct
80 Correct 106 ms 13036 KB Output is correct
81 Correct 102 ms 13036 KB Output is correct
82 Correct 1538 ms 13292 KB Output is correct
83 Correct 1500 ms 13292 KB Output is correct
84 Correct 105 ms 13036 KB Output is correct
85 Correct 1489 ms 13420 KB Output is correct
86 Correct 102 ms 13036 KB Output is correct
87 Correct 1491 ms 13348 KB Output is correct
88 Correct 102 ms 13068 KB Output is correct
89 Correct 1488 ms 13420 KB Output is correct
90 Correct 101 ms 13036 KB Output is correct
91 Correct 1509 ms 13292 KB Output is correct
92 Correct 101 ms 13036 KB Output is correct
93 Correct 1474 ms 13424 KB Output is correct
94 Correct 90 ms 13036 KB Output is correct
95 Correct 811 ms 13292 KB Output is correct
96 Correct 819 ms 13292 KB Output is correct
97 Correct 1527 ms 13344 KB Output is correct
98 Correct 1509 ms 13568 KB Output is correct