Submission #694560

#	Time	Username	Problem	Language	Result	Execution time	Memory
694560		Do_you_copy	Construction of Highway (JOI18_construction)	C++17	100 / 100	417 ms	106992 KiB

construction

//Then
#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define faster ios_base::sync_with_stdio(0); cin.tie(0);

using namespace std;
using ll = long long;
using ld = long double;
using pii = pair <int, int>;
mt19937_64 Rand(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 1e5 + 1;
//const int Mod = 1e9 + 7;
//const int inf =
int n;
int a[maxN], b[maxN], c[maxN];

struct TSeg{
    int l, r, t;
};

deque <TSeg> S[maxN];
vector <int> adj[maxN];
int head[maxN], id[maxN], num[maxN];
int child[maxN], depth[maxN], par[maxN];
int timedfs, cnt = 1;
vector <int> node;
struct TBIT{
    int bit[maxN];
    TBIT(){
        memset(bit, 0, sizeof(bit));
    }
    void update(int x, int v){
        for (; x <= n; x += x & -x){
            bit[x] += v;
        }
    }
    int get(int x){
        int res = 0;
        for (; x; x -= x & -x){
            res += bit[x];
        }
        return res;
    }
};
TBIT bit;
void dfs(int u, int p){
    depth[u] = depth[p] + 1;
    par[u] = p;
    for (int i: adj[u]){
        dfs(i, u);
        child[u] += child[i] + 1;
    }
}

void hld(int u){
    num[u] = ++timedfs;
    if (!head[cnt]) head[cnt] = u;
    id[u] = cnt;
    pii maxx = {-1, -1};
    for (int i: adj[u]){
        maxx = max(maxx, {child[i], i});
    }
    if (maxx.se != -1){
        hld(maxx.se);
    }
    for (int i: adj[u]){
        if (i == maxx.se) continue;
        ++cnt;
        hld(i);
    }
}

ll query(int u, int v){
    ll res = 0;
    vector <TSeg> save;
    while (u){
        int p = id[u];
        vector <TSeg> tem;
        while (!S[p].empty() && S[p].back().r <= num[u]){
            tem.pb(S[p].back());
            S[p].pop_back();
        }
        if (!S[p].empty() && S[p].back().l <= num[u]){
            tem.pb({S[p].back().l, num[u], S[p].back().t});
            S[p].back().l = num[u] + 1;
        }
        reverse(tem.begin(), tem.end());
        for (auto i: tem){
            res += 1LL * (i.r - i.l + 1) * bit.get(i.t - 1);
            bit.update(i.t, i.r - i.l + 1);
        }
        move(tem.begin(), tem.end(), back_inserter(save));
        S[p].pb({num[head[p]], num[u], c[v]});
        u = par[head[p]];
    }
    for (auto i: save){
        bit.update(i.t, i.l - i.r - 1);
    }
    S[id[v]].push_front({num[v], num[v], c[v]});
    return res;
}

void Init(){
    cin >> n;
    for (int i = 1; i <= n; ++i){
        cin >> c[i];
        node.pb(c[i]);
    }
    sort(node.begin(), node.end());
    node.resize(unique(node.begin(), node.end()) - node.begin());
    for (int i = 1; i <= n; ++i){
        c[i] = upper_bound(node.begin(), node.end(), c[i]) - node.begin();
    }
    for (int i = 1; i < n; ++i){
        cin >> a[i] >> b[i];
        adj[a[i]].pb(b[i]);
    }
    dfs(1, 0);
    hld(1);
    S[1].pb({1, 1, c[1]});
    for (int i = 1; i < n; ++i){
        cout << query(a[i], b[i]) << "\n";
    }
}

#define debug
#define taskname "test"
signed main(){
    faster
    if (fopen(taskname".inp", "r")){
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    int tt = 1;
    //cin >> tt;
    while (tt--){
        Init();
    }
    if (fopen("timeout.txt", "r")){
        ofstream timeout("timeout.txt");
        timeout << signed(double(clock()) / CLOCKS_PER_SEC * 1000);
        timeout.close();
        #ifndef debug
        cerr << "Time elapsed: " << signed(double(clock()) / CLOCKS_PER_SEC * 1000) << "ms\n";
        #endif // debug
    }
}

Compilation message (stderr)

construction.cpp: In function 'int main()':
construction.cpp:133:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  133 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
construction.cpp:134:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  134 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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