Submission #976768

#	Time	Username	Problem	Language	Result	Execution time	Memory
976768		gaga999	Bridges (APIO19_bridges)	C++17	100 / 100	1266 ms	5068 KiB

bridges

// #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 __int128_t lll;
typedef pair<int, int> pii;
typedef pair<double, double> pdd;
typedef pair<llt, llt> pll;
typedef pair<llt, int> pli;
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 = 1e5 + 5, B = 1000;
int x[N], y[N], w[N], op[N], a[N], b[N], od[N], ds[N], an[N];
bool vd[N], ud[N];
vector<pii> rm;

int f(int k)
{
    return ds[k] < 0 ? k : f(ds[k]);
}

void mg(int i, int j)
{
    i = f(i), j = f(j);
    if (i != j)
    {
        if (ds[i] > ds[j])
            swap(i, j);
        rm.pb(ds[j], j);
        ds[i] += ds[j], ds[j] = i;
    }
}

inline void undo(int ln)
{
    while (size(rm) > ln)
        ds[ds[rm.back().S]] -= rm.back().F,
            ds[rm.back().S] = rm.back().F,
            rm.pop_back();
}

signed main()
{
    int n, m, q;
    rd(n, m);
    for (int i = 1; i <= m; i++)
        rd(x[i], y[i], w[i]);
    rd(q);
    for (int i = 0; i < q; i++)
        rd(op[i], a[i], b[i]);
    iota(od, od + m, 1);
    for (int l = 0; l < q; l += B)
    {
        int r = min(l + B, q);
        vector<int> cb, cq;
        for (int i = l; i < r; i++)
        {
            if (op[i] == 1) // 1 bridge number / new weight
                cb.pb(a[i]), vd[a[i]] = 1;
            else // 2 island number / weight
                cq.pb(i);
        }
        sort(iter(cb)), uni(cb);
        init(ds, -1), rm.clear();
        sort(od, od + m, [&](int i, int j)
             { return w[i] > w[j]; });
        sort(iter(cq), [&](int i, int j)
             { return b[i] > b[j]; });
        int p = 0;
        for (int k : cq)
        {
            while (p < m && w[od[p]] >= b[k])
            {
                if (!vd[od[p]])
                    mg(x[od[p]], y[od[p]]);
                p++;
            }
            int ln = size(rm);
            for (int i = k; i >= l; i--)
            {
                if (op[i] == 2 || ud[a[i]])
                    continue;
                ud[a[i]] = 1;
                if (b[i] >= b[k])
                    mg(x[a[i]], y[a[i]]);
            }
            for (int i : cb)
            {
                if (ud[i])
                    ud[i] = 0;
                else if (w[i] >= b[k])
                    mg(x[i], y[i]);
            }
            an[k] = -ds[f(a[k])];
            undo(ln);
        }
        for (int i = l; i < r; i++)
            if (op[i] == 1)
                vd[a[i]] = 0, w[a[i]] = b[i];
    }
    for (int i = 0; i < q; i++)
        if (op[i] == 2)
            prt(an[i]), putchar('\n');
}

• Subtask 1: 13 / 13
• Subtask 2: 16 / 16
• Subtask 3: 17 / 17
• Subtask 4: 14 / 14
• Subtask 5: 13 / 13
• Subtask 6: 27 / 27