Submission #933339

#	Time	Username	Problem	Language	Result	Execution time	Memory
933339		parlimoos	Construction of Highway (JOI18_construction)	C++14	100 / 100	500 ms	34260 KiB

construction

//Be Name KHODA
#pragma GCC optimize("Ofast")
#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
#define pb push_back
#define pp pop_back
#define lb lower_bound
#define ub upper_bound
#define cl clear
#define bg begin
#define arr(x) array<int , x>
#define endl '\n'


int n;
vector<int> a , cmp;
int tms[100000] , cs[100000] , hs[100000];
int pth[100000] , bl[100000][20];
int seg[400001][2] , seginf[400001][2] , is[100000];
int fen[100001];
int segcnt = 0;
vector<int> tr[100000];
vector<arr(2)> ops;
vector<arr(2)> ns;

int timer = -1;
void dfs1(int v = 0 , int p = -1){
    cs[v] = 1 , bl[v][0] = p;
    if(p != -1) hs[v] = hs[p] + 1;
    for(int i = 1 ; i < 20 ; i++){
        if(bl[v][i - 1] == -1) bl[v][i] = -1;
        else bl[v][i] = bl[bl[v][i - 1]][i - 1];
    }
    for(int u : tr[v]) if(u != p) dfs1(u , v) , cs[v] += cs[u];
}
void hld(int v = 0){
    tms[v] = ++timer;
    int mxi = -1;
    for(int u : tr[v]) if(u != bl[v][0] and (mxi == -1 or cs[mxi] < cs[u])) mxi = u;
    if(mxi == -1) return;
    pth[mxi] = pth[v] , hld(mxi);
    for(int u : tr[v]) if(u != bl[v][0] and u != mxi) pth[u] = u , hld(u);
}
void buildSeg(int l = 0 , int r = n - 1 , int i = 1){
    seginf[i][0] = l , seginf[i][1] = r , seg[i][1] = -1;
    if(l == r) is[l] = i;
    else{
        int c = (r + l - 1) >> 1;
        buildSeg(l , c , i << 1) , buildSeg(c + 1 , r , (i << 1) | 1);
    }
}
void updSeg(int l , int r , int i , int val){
    if(seginf[i][0] >= l and seginf[i][1] <= r) seg[i][0] = val , seg[i][1] = segcnt;
    else if(seginf[i][1] >= l and seginf[i][0] <= r) updSeg(l , r , i << 1 , val) , updSeg(l , r , (i << 1) | 1 , val);
}
arr(2) getSeg(int v){
    int i = is[tms[v]] , res = seg[i][0] , time = seg[i][1];
    while(i > 1){
        i >>= 1;
        if(time < seg[i][1]) time = seg[i][1] , res = seg[i][0];
    }
    return {res , time};
}
void cmpInt(){
    cmp = a;
    sort(cmp.bg() , cmp.end());
    cmp.resize(int(unique(cmp.bg() , cmp.end()) - cmp.bg()));
    for(int &el : a) el = int(lb(cmp.bg() , cmp.end() , el) - cmp.bg());
}
void addFen(int i , int val){
    i++;
    while(i < n + 1) fen[i] += val , i += (i & (-i));
}
int getFen(int l , int r){
    int res = 0;
    r++;
    while(r > 0) res += fen[r] , r -= (r & (-r));
    while(l > 0) res -= fen[l] , l -= (l & (-l));
    return res;
}
void updPth(int v , int val){
    while(v != -1){
        updSeg(tms[pth[v]] , tms[v] , 1 , val);
        v = bl[pth[v]][0];
    }
    segcnt++;
}
ll getPth(int v){
    ns.cl();
    ll res = 0;
    while(v != -1){
        auto d = getSeg(v);
        int u = v;
        for(int i = 19 ; i >= 0 ; i--){
            if(bl[u][i] == -1) continue;
            if(getSeg(bl[u][i]) == d) u = bl[u][i];
        }
        ns.pb({d[0] , hs[v] - hs[u] + 1});
        v = bl[u][0];
    }
    for(int i = 0 ; i < (int)ns.size() ; i++){
        if(ns[i][0] > 0) res += (1ll * ns[i][1]) * (1ll * getFen(0 , ns[i][0] - 1));
        addFen(ns[i][0] , ns[i][1]);
    }
    for(int i = 0 ; i < (int)ns.size() ; i++) addFen(ns[i][0] , -(ns[i][1]));
    return res;
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);

    cin >> n;
    for(int i = 0 ; i < n ; i++){
        int d;
        cin >> d;
        a.pb(d);
    }
    for(int i = 1 ; i < n ; i++){
        int v , u;
        cin >> v >> u;
        v-- , u--;
        tr[v].pb(u) , tr[u].pb(v);
        ops.pb({v , u});
    }
    dfs1() , hld() , cmpInt() , buildSeg();
    for(auto op : ops){
        ll o = getPth(op[0]);
        cout << o << endl;
        updPth(op[1] , a[op[1]]);
    }
}

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