Submission #1048628

#	Time	Username	Problem	Language	Result	Execution time	Memory
1048628		Nonoze	Graph (BOI20_graph)	C++17	58 / 100	586 ms	22980 KiB

Graph

/*
*	Author: Nonoze
*	Created: Wednesday 07/08/2024
*/
#include <bits/stdc++.h>
using namespace std;

namespace std {

// https://judge.yosupo.jp/submission/193613
struct IOPre {
    static constexpr int TEN = 10, SZ = TEN * TEN * TEN * TEN;
    std::array<char, 4 * SZ> num;
    constexpr IOPre() : num{} {
        for (int i = 0; i < SZ; i++) for (int n = i, j = 3; j >= 0; j--) num[i * 4 + j] = n % TEN + '0', n /= TEN;
    }
};

struct IO {
#if !HAVE_DECL_FREAD_UNLOCKED
    #define fread_unlocked fread
#endif
#if !HAVE_DECL_FWRITE_UNLOCKED
    #define fwrite_unlocked fwrite
#endif
    static constexpr int SZ = 1 << 17, LEN = 32, TEN = 10, HUNDRED = TEN * TEN,
                         THOUSAND = HUNDRED * TEN, TENTHOUSAND = THOUSAND * TEN,
                         MAGIC_MULTIPLY = 205, MAGIC_SHIFT = 11, MASK = 15,
                         TWELVE = 12, SIXTEEN = 16;
    static constexpr IOPre io_pre = {};
    std::array<char, SZ> input_buffer, output_buffer;
    int input_ptr_left, input_ptr_right, output_ptr_right;

    IO() : input_buffer{}, output_buffer{}, input_ptr_left{}, input_ptr_right{}, output_ptr_right{} {}
    IO(const IO&) = delete;
    IO(IO&&) = delete;
    IO& operator=(const IO&) = delete;
    IO& operator=(IO&&) = delete;
    ~IO() { flush(); }

    template<typename T> static constexpr bool is_char_v    = std::is_same_v<T, char>;
    template<typename T> static constexpr bool is_bool_v    = std::is_same_v<T, bool>;
    template<typename T> static constexpr bool is_string_v  =
            std::is_same_v<T, std::string> || std::is_same_v<T, const char*> ||
            std::is_same_v<T, char*> || std::is_same_v< std::decay_t<T>, char*>;
    template<typename T> static constexpr bool is_default_v =
            is_char_v<T> || is_bool_v<T> || is_string_v<T> || std::is_integral_v<T>;

    inline void load() {
        memmove(std::begin(input_buffer),
                std::begin(input_buffer) + input_ptr_left,
                input_ptr_right - input_ptr_left);
        input_ptr_right =
            input_ptr_right - input_ptr_left +
            fread_unlocked(
                std::begin(input_buffer) + input_ptr_right - input_ptr_left, 1,
                SZ - input_ptr_right + input_ptr_left, stdin);
        input_ptr_left = 0;
    }

    inline void read_char(char& c) {
        if (input_ptr_left + LEN > input_ptr_right) load();
        c = input_buffer[input_ptr_left++];
    }
    inline void read_string(std::string& x) {
        char c;
        while (read_char(c), c < '!') continue;
        x = c;
        while (read_char(c), c >= '!') x += c;
    }
    template<typename T>
    inline std::enable_if_t<std::is_integral_v<T>, void> read_int(T& x) {
        if (input_ptr_left + LEN > input_ptr_right) load();
        char c = 0;
        do c = input_buffer[input_ptr_left++];
        while (c < '-');
        [[maybe_unused]] bool minus = false;
        if constexpr (std::is_signed<T>::value == true)
            if (c == '-') minus = true, c = input_buffer[input_ptr_left++];
        x = 0;
        while (c >= '0')
            x = x * TEN + (c & MASK), c = input_buffer[input_ptr_left++];
        if constexpr (std::is_signed<T>::value == true)
            if (minus) x = -x;
    }

    inline void skip_space() {
        if (input_ptr_left + LEN > input_ptr_right) load();
        while (input_buffer[input_ptr_left] <= ' ') input_ptr_left++;
    }

    inline void flush() {
        fwrite_unlocked(std::begin(output_buffer), 1, output_ptr_right, stdout);
        output_ptr_right = 0;
    }

    inline void write_char(char c) {
        if (output_ptr_right > SZ - LEN) flush();
        output_buffer[output_ptr_right++] = c;
    }

    inline void write_bool(bool b) {
        if (output_ptr_right > SZ - LEN) flush();
        output_buffer[output_ptr_right++] = b ? '1' : '0';
    }

    inline void write_string(const std::string& s) {
        for (auto x : s) write_char(x);
    }

    inline void write_string(const char* s) {
        while (*s) write_char(*s++);
    }

    inline void write_string(char* s) {
        while (*s) write_char(*s++);
    }

    template <typename T>
    inline std::enable_if_t< std::is_integral_v<T>, void> write_int(T x) {
        if (output_ptr_right > SZ - LEN) flush();
        if (!x) {
            output_buffer[output_ptr_right++] = '0';
            return;
        }
        if constexpr (std::is_signed_v<T>) if (x < 0) output_buffer[output_ptr_right++] = '-', x = -x;
        int i = TWELVE;
        std::array<char, SIXTEEN> buf{};
        for (; x >= TENTHOUSAND; x /= TENTHOUSAND, i -= 4)
            memcpy(std::begin(buf) + i, std::begin(io_pre.num) + (x % TENTHOUSAND) * 4, 4);
        if (x < HUNDRED) {
            if (x < TEN) output_buffer[output_ptr_right++] = '0' + x;
            else {
                uint32_t q = (uint32_t(x) * MAGIC_MULTIPLY) >> MAGIC_SHIFT;
                uint32_t r = uint32_t(x) - q * TEN;
                output_buffer[output_ptr_right++] = '0' + q;
                output_buffer[output_ptr_right++] = '0' + r;
            }
        } else {
            if (x < THOUSAND) 
                memcpy(std::begin(output_buffer) + output_ptr_right, std::begin(io_pre.num) + (x << 2) + 1, 3),
                output_ptr_right += 3;
            else
                memcpy(std::begin(output_buffer) + output_ptr_right, std::begin(io_pre.num) + (x << 2), 4),
                output_ptr_right += 4;
        }
        memcpy(std::begin(output_buffer) + output_ptr_right, std::begin(buf) + i + 4, TWELVE - i);
        output_ptr_right += TWELVE - i;
    }

    template <typename T_>
    std::enable_if_t<(is_default_v< std::remove_cv_t< std::remove_reference_t<T_> > >), IO&> operator<<(T_&& x) {
        using T = std::remove_cv_t< std::remove_reference_t<T_> >;
        if constexpr (is_bool_v<T>) write_bool(x);
        else if constexpr (is_string_v<T>) write_string(x);
        else if constexpr (is_char_v<T>) write_char(x);
        else if constexpr (std::is_integral_v<T>) write_int(x);
        return *this;
    }

    template<typename T>
    std::enable_if_t<(is_default_v<T> && !is_bool_v<T>), IO&> operator>>(T& x) {
        if constexpr (is_string_v<T>) read_string(x);
        else if constexpr (is_char_v<T>) read_char(x);
        else if constexpr (std::is_integral_v<T>) read_int(x);
        return *this;
    }

    IO* tie(std::nullptr_t) { return this; }
    void sync_with_stdio(bool) {}
} io;

} // namespace std

using std::io;

#define cin io

#ifndef _IN_LOCAL
	#define dbg(...)
#endif

#define endl '\n'
#define endlfl '\n' << flush
#define quit(x) return (void)(cout << x << endl)

#define sz(x) (int)(x.size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define cmin(a, b) a = min(a, b)
#define cmax(a, b) a = max(a, b)

#define int long long
const int inf = numeric_limits<int>::max() / 4;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MOD = 1e9+7, LOG=25;



void solve();

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	int tt=1;
	// cin >> tt;
	while(tt--) solve();
	return 0;
}




int n, k, m, q;
vector<pair<int, int>> adj[100000];
bool visited[100000];
double weights[100000];

vector<vector<int>> contains;
vector<int> roots;

void dfspre(int u) {
	visited[u]=1;
	contains.back().pb(u);
	for (auto [v, w] : adj[u]) if (!visited[v]) dfspre(v);
}

void precalc() {
	vector<int> a(n); iota(all(a), 0);
	shuffle(all(a), rng);
	for (int i: a) if (!visited[i]) {
		roots.pb(i);
		contains.pb({});
		dfspre(i);
	}
}


double dfs(int u) {
	visited[u]=1;
	double act=abs(weights[u]);
	for (auto [v, w]: adj[u]) {
		if (weights[v]!=-inf && weights[v]+weights[u]!=w) return inf;
		if (weights[v]!=-inf) continue;
		weights[v]=w-weights[u];
		double t=dfs(v);
		if (t==inf) return inf;
		act+=t;
	}
	return act;
}

double calcw(int src, int empl, double w) {
	for (auto u: contains[empl]) weights[u]=-inf;
	weights[src]=w;
	return dfs(src);
}

void calc(int src, int empl) {
	int l=-500, r=500, ans=0;
	while (l<=r) {
		int m1=l+(r-l)/3, m2=r-(r-l)/3;
		double t1=calcw(src, empl, (double)m1/2), t2=calcw(src, empl, (double)m2/2);
		if (t1<t2) r=m2-1, ans=m2;
		else l=m1+1, ans=m1;
	}
	double t=(double)ans/2;
}

void solve() {
	cin >> n >> m;
	for (int i=0; i<m; i++) {
		int u, v, w; cin >> u >> v >> w; u--, v--;
		adj[u].pb({v, w});
		adj[v].pb({u, w});
	}
	precalc();
	for (int i=0; i<n; i++) weights[i]=-inf;
	int empl=0;
	for (auto src: roots) {
		if (calcw(src, empl, 0)!=inf && calcw(src, empl, 0.5)!=inf) {
			calc(src, empl);
			empl++;
			continue;
		}
		bool ok=0;
		for (double t=-150; t<=150; (t>=-25&&t<25?t+=0.5:t++)) {
			if (calcw(src, empl, t)!=inf) {ok=1; break;}
		}
		if (!ok) quit("NO");
		empl++;
	}
	double ans=0;
	cout << "YES" << fixed << setprecision(8) << endl;
	for (int i=0; i<n; i++) cout << weights[i] << ' ';
}

Compilation message (stderr)

Graph.cpp: In function 'void calc(long long int, long long int)':
Graph.cpp:271:9: warning: unused variable 't' [-Wunused-variable]
  271 |  double t=(double)ans/2;
      |         ^
Graph.cpp: In function 'void solve()':
Graph.cpp:297:9: warning: unused variable 'ans' [-Wunused-variable]
  297 |  double ans=0;
      |         ^~~

• Subtask 1: 5 / 5
• Subtask 2: 12 / 12
• Subtask 3: 17 / 17
• Subtask 4: 24 / 24
• Subtask 5: 0 / 42