Submission #952733

# Submission time Handle Problem Language Result Execution time Memory
952733 2024-03-24T16:28:06 Z gaga999 Mountains and Valleys (CCO20_day1problem3) C++17
2 / 25
29 ms 111452 KB
// #pragma GCC optimize("Ofast,no-stack-protector")
// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx,avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
#define lowbit(x) ((x) & -(x))
#define ml(a, b) ((1ll * (a) * (b)) % M)
#define tml(a, b) (a) = ((1ll * (a) * (b)) % M)
#define ad(a, b) ((0ll + (a) + (b)) % M)
#define tad(a, b) (a) = ((0ll + (a) + (b)) % M)
#define mi(a, b) ((0ll + M + (a) - (b)) % M)
#define tmi(a, b) (a) = ((0ll + M + (a) - (b)) % M)
#define tmin(a, b) (a) = min((a), (b))
#define tmax(a, b) (a) = max((a), (b))
#define iter(a) (a).begin(), (a).end()
#define riter(a) (a).rbegin(), (a).rend()
#define init(a, b) memset((a), (b), sizeof(a))
#define cpy(a, b) memcpy((a), (b), sizeof(a))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define size(x) (int)x.size()
#define pb emplace_back
#define mpr make_pair
#define ls(i) ((i) << 1)
#define rs(i) ((i) << 1 | 1)
#define INF 0x3f3f3f3f
#define NIF 0xc0c0c0c0
#define eps 1e-9
#define F first
#define S second
#define AC cin.tie(0)->sync_with_stdio(0)
using namespace std;
typedef long long llt;
typedef pair<int, int> pii;
typedef pair<double, double> pdd;
typedef pair<llt, llt> pll;
typedef complex<double> cd;
// const int M = 998244353;

// random_device rm;
// mt19937 rg(rm());
// default_random_engine rg(rm());
// uniform_int_distribution<int> rd(INT_MIN, INT_MAX);
// uniform_real_distribution<double> rd(0, M_PI);

void db() { cerr << "\n"; }
template <class T, class... U>
void db(T a, U... b) { cerr << a << " ", db(b...); }

inline char gc()
{
    const static int SZ = 1 << 16;
    static char buf[SZ], *p1, *p2;
    if (p1 == p2 && (p2 = buf + fread(p1 = buf, 1, SZ, stdin), p1 == p2))
        return -1;
    return *p1++;
}
void rd() {}
template <typename T, typename... U>
void rd(T &x, U &...y)
{
    x = 0;
    bool f = 0;
    char c = gc();
    while (!isdigit(c))
        f ^= !(c ^ 45), c = gc();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ 48), c = gc();
    f && (x = -x), rd(y...);
}

template <typename T>
void prt(T x)
{
    if (x < 0)
        putchar('-'), x = -x;
    if (x > 9)
        prt(x / 10);
    putchar((x % 10) ^ 48);
}

const int N = 5e5 + 5, M = 2e6 + 6;
vector<int> eg[N];
int xr[M], yr[M], wr[M], a1[M];
int in[N], ou[N], ct, ac[20][N];
int mx[N], sc[N], dp[N], ans, bs;
vector<int> q1[N], q2[N];

void dfs(int u, int fa)
{
    in[u] = ++ct;
    for (int v : eg[u])
    {
        if (v == fa)
            continue;
        ac[0][v] = u, dp[v] = dp[u] + 1;
        for (int i = 1; i < 20; i++)
            ac[i][v] = ac[i - 1][ac[i - 1][v]];
        dfs(v, u);
        tmax(sc[u], mx[v] + 1);
        if (sc[u] > mx[u])
            swap(mx[u], sc[u]);
    }
    tmax(ans, mx[u] + sc[u]), ou[u] = ct;
}

inline bool isa(int a, int p)
{
    return in[a] <= in[p] && ou[p] <= ou[a];
}

inline int lca(int u, int v)
{
    if (isa(u, v))
        return u;
    for (int i = 19; i >= 0; i--)
        if (ac[i][u] && !isa(ac[i][u], v))
            u = ac[i][u];
    return ac[0][u];
}

struct P
{
    int vp, vn, ans;
    P() { vp = vn = ans = -INF; }
    inline void ini() { vp = vn = ans = -INF; }
    P operator+(const P &rh)
    {
        P res;
        res.ans = max({ans, vp + rh.vn, rh.ans});
        res.vp = max(vp, rh.vp);
        res.vn = max(vn, rh.vn);
        return res;
    }
} tr[N << 2], vv;

void cg(int l, int r, int id, int p, int v)
{
    if (l == r)
    {
        tr[id].vp = v + p;
        tr[id].vn = v - p;
        tr[id].ans = -INF;
        return;
    }
    int m = (l + r) >> 1;
    if (p <= m)
        cg(l, m, ls(id), p, v);
    else
        cg(m + 1, r, rs(id), p, v);
    tr[id] = tr[ls(id)] + tr[rs(id)];
}

void qy(int l, int r, int id, int ql, int qr)
{
    if (ql <= l && r <= qr)
    {
        vv = vv + tr[id];
        return;
    }
    int m = (l + r) >> 1;
    if (ql <= m)
        qy(l, m, ls(id), ql, qr);
    if (qr > m)
        qy(m + 1, r, rs(id), ql, qr);
}

void slv(int u, int fa)
{
    for (int v : eg[u])
    {
        if (v == fa)
            continue;
        cg(1, ct, 1, dp[u], mx[v] + 1 == mx[u] ? sc[u] : mx[u]);
        slv(v, u);
    }
    cg(1, ct, 1, dp[u], mx[u]);
    for (int i : q1[u])
    {
        vv.ini(), qy(1, ct, 1, dp[xr[i]], dp[u]);
        tmin(ans, bs + wr[i] - (vv.ans + dp[u] - dp[xr[i]]));
        vv.ini(), qy(1, ct, 1, dp[xr[i]] + 1, dp[u]);
        int tp = vv.vn + dp[u] + dp[xr[i]];
        vv.ini(), qy(1, ct, 1, 1, dp[xr[i]]);
        tmin(ans, bs + wr[i] - (tp + vv.vn));
    }
    for (int i : q2[u])
    {
        int p = lca(xr[i], yr[i]);
        vv.ini(), qy(1, ct, 1, dp[p], dp[u]);
        // assert(dp[p] != dp[u]);
        // tmin(ans, bs + wr[i] -
        //               (vv.ans + dp[xr[i]] + dp[yr[i]] - (dp[p] << 1)));
        vv.ini(), qy(1, ct, 1, dp[p] + 1, dp[u]);
        if (xr[i] == u)
            a1[i] = vv.vn;
        else
            tmin(ans, bs + wr[i] - (vv.vn + a1[i] + dp[xr[i]] + dp[yr[i]]));
    }
}

signed main()
{
    int n, m;
    rd(n, m), bs = (n - 2) << 1;
    for (int i = 0; i < m; i++)
    {
        rd(xr[i], yr[i], wr[i]), xr[i]++, yr[i]++;
        if (wr[i] == 1)
            eg[xr[i]].pb(yr[i]), eg[yr[i]].pb(xr[i]);
    }
    int rt = 6;
    dp[rt] = 1, dfs(rt, -1), ans = ((n - 1) << 1) - ans;
    int pans = ans;
    for (int i = 0; i < m; i++)
    {
        assert(xr[i] != yr[i]);
        if (wr[i] == 1)
            continue;
        if (in[xr[i]] > in[yr[i]])
            swap(xr[i], yr[i]);
        if (isa(xr[i], yr[i]))
            q1[yr[i]].pb(i);
        else
            q2[xr[i]].pb(i), q2[yr[i]].pb(i);
    }
    slv(rt, -1);
    assert(ans <= pans);
    prt(ans), putchar('\n');
}
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 69576 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 69576 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 26 ms 111108 KB Output is correct
2 Correct 25 ms 111452 KB Output is correct
3 Correct 26 ms 111184 KB Output is correct
4 Correct 25 ms 111196 KB Output is correct
5 Correct 29 ms 111188 KB Output is correct
6 Correct 29 ms 111196 KB Output is correct
7 Correct 25 ms 111452 KB Output is correct
8 Correct 26 ms 111188 KB Output is correct
9 Correct 25 ms 111452 KB Output is correct
10 Correct 25 ms 111408 KB Output is correct
11 Correct 25 ms 111452 KB Output is correct
12 Correct 27 ms 111284 KB Output is correct
13 Correct 25 ms 111196 KB Output is correct
14 Correct 28 ms 111196 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 69576 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 69576 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 69576 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 69576 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 15 ms 69576 KB Output isn't correct
2 Halted 0 ms 0 KB -