제출 #1290266

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1290266		vuquangsang	Construction of Highway (JOI18_construction)	C++20	100 / 100	332 ms	19496 KiB

construction

#include <bits/stdc++.h>
using namespace std;

#define     el "\n"
#define     FOR(i,a,b) for(int i = (a), _b = (b); i <= _b; i++)
#define     FORD(i,a,b) for(int i = (a), _b = (b); i >= _b; i--)
#define     pb push_back
#define     fi first
#define     se second
#define     all(x) x.begin(),x.end()
#define     lg(x) __lg(x)
#define     alla(a,n) a+1,a+n+1
#define     ll long long


template <class T> bool maxi(T &x, T y) { if(x < y) { x = y ; return true ;} return false;}
template <class T> bool mini(T &x, T y) { if(x > y) { x = y ; return true ;} return false;}

const int N = 1e5 + 2;

int n, a[N];
vector<int> adj[N];
pair<int, int> E[N];

void compress()
{
    vector<int> V;
    FOR(i, 1, n) V.push_back(a[i]);
    sort(all(V));
    V.resize(unique(all(V)) - V.begin());
    FOR(i, 1, n) {
        a[i] = lower_bound(all(V), a[i]) - V.begin() + 1;
    }
}
void inp()
{
    cin >> n;
    FOR(i, 1, n) cin >> a[i];
    FOR(i, 1, n - 1) {
        int x, y; cin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
        E[i] = {x, y};
    }
    compress();
}


namespace subtask_1
{

    int h[N], par[N];

    void dfs(int u, int p)
    {
        for(int v : adj[u]) if(v != p) {
            h[v] = h[u] + 1;
            par[v] = u;
            dfs(v, u);
        }
    }

    int calc(int x)
    {
        int ans = 0;
        int cur = x;
        while(cur > 0) {
            if(a[cur] > a[x]) ans++;
            cur = par[cur];
        }
        return ans;
    }
    void slv()
    {
        dfs(1, 1);
        FOR(i, 1, n - 1) {
            int x = E[i].first, y = E[i].second;

            int cur = x;
            int ans = 0;
            while(cur > 0) {
                ans += calc(cur);
                cur = par[cur];
            }
            cur = x;
            while(cur > 0) {
                a[cur] = a[y];
                cur = par[cur];
            }
            cout << ans << el;
        }
    }
}

namespace subtask_12
{
    int bit[N];

    void upd(int x, int v)
    {
        for(; x <= n; x += x & -x) bit[x] += v;
    }
    int get(int x)
    {
        int ans = 0;
        for(; x >= 1; x -= x & -x) ans += bit[x];
        return ans;
    }
    int h[N], par[N];

    void dfs(int u, int p)
    {
        for(int v : adj[u]) if(v != p) {
            h[v] = h[u] + 1;
            par[v] = u;
            dfs(v, u);
        }
    }
    void slv()
    {
        dfs(1, 1);
        FOR(i, 1, n - 1) {
            int x = E[i].first, y = E[i].second;
            memset(bit, 0, sizeof bit);

            int ans = 0;
            int cur = x;
            while(cur > 0) {
                ans += get(a[cur] - 1);
                upd(a[cur], 1);
                cur = par[cur];
            }
            cur = x;
            while(cur > 0) {
                a[cur] = a[y];
                cur = par[cur];
            }
            cout << ans << el;
        }
    }
}

// subtask_3 -> source by watbor
namespace subtask_3
{

    int sz[N], h[N], par[N];

    void dfs(int u, int p)
    {
        sz[u] = 1;
        for(int v : adj[u]) if(v != p) {
            h[v] = h[u] + 1;
            par[v] = u;
            dfs(v, u);
            sz[u] += sz[v];
        }
    }
    int head[N], chainID[N], mtc = 1, time = 0, pos[N], euler[N];

    void hld(int u, int p)
    {
        if(!head[mtc]) {
            head[mtc] = u;
        }
        chainID[u] = mtc;

        euler[++time] = u;
        pos[u] = time;

        int ma = 0;
        for(int v : adj[u]) if(v != p) {
            if(!ma || sz[v] > sz[ma]) ma = v;
        }
        if(ma) hld(ma, u);

        for(int v : adj[u]) if(v != p && v != ma) {
            mtc++;
            hld(v, u);
        }
    }

    int st[4 * N];
    int bit[N];

    void upd(int x, int v)
    {
        for(; x <= n; x += x & -x) bit[x] += v;
    }
    int get(int x)
    {
        int ans = 0;
        for(; x >= 1; x -= x & -x) ans += bit[x];
        return ans;
    }

    void down(int id)
    {
        if(st[id] == -1) return;
        st[id << 1] = st[id << 1 | 1] = st[id];
    }
    void upd(int id, int l, int r, int u, int v, int val)
    {
        if(r < u || v < l) return;
        if(u <= l && r <= v) {
            st[id] = val;
            return;
        }
        int mid = (r + l) >> 1;
        down(id);

        upd(id << 1, l, mid, u, v, val);
        upd(id << 1 | 1, mid + 1, r, u, v, val);

        if(st[id << 1] == st[id << 1 | 1]) st[id] = st[id << 1];
        else st[id] = -1;
    }

    stack<pair<int, int>> memo;
    int get(int id, int l, int r, int u, int v)
    {
        if(r < u || v < l) return 0;
        if(u <= l && r <= v && st[id] != -1) {
            int res = (r - l + 1) * get(st[id] - 1);
            upd(st[id], r - l + 1);
            memo.push({st[id], r - l + 1});
            return res;
        }
        int mid = (r + l) >> 1;
        down(id);
        return get(id << 1 | 1, mid + 1, r, u, v) + get(id << 1, l, mid, u, v);
    }

    int calc(int u)
    {
        upd(1, 1, n, pos[u], pos[u], a[u]);
        int val = a[u];

        u = par[u];

        int ans = 0;
        while(u > 0) {
            ans += get(1, 1, n, pos[head[chainID[u]]], pos[u]);
            upd(1, 1, n, pos[head[chainID[u]]], pos[u], val);
            u = par[head[chainID[u]]];
        }

        while(!memo.empty()) {
            int pos = memo.top().first;
            int val = memo.top().second;
            memo.pop();
            upd(pos, -val);
        }

        return ans;

    }
    void slv()
    {
        dfs(1, 1);
        hld(1, 1);

        memset(st, -1, sizeof st);

        calc(1);
        FOR(i, 1, n - 1) {
            int u = E[i].second;
            cout << calc(u) << el;
        }
    }
}

main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);

    #define __Azul__ "JOI18_construction"
    if(fopen(__Azul__".inp", "r")) {
        freopen(__Azul__".inp", "r", stdin);
        freopen(__Azul__".out", "w", stdout);
    }

    bool qs = 0;

    int T = 1;
    if(qs) cin >> T;
    while(T--) {
        inp();

        subtask_3 :: slv(); return 0;

        if(n <= 4000) subtask_12::slv();
        else subtask_3 :: slv();
    }

    cerr << "\nTime" << 0.001 * clock() << "s "; return 0;


}

컴파일 시 표준 에러 (stderr) 메시지

construction.cpp:273:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  273 | main()
      | ^~~~
construction.cpp: In function 'int main()':
construction.cpp:279:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  279 |         freopen(__Azul__".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
construction.cpp:280:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  280 |         freopen(__Azul__".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 9 / 9
• Subtask 3: 84 / 84