Submission #1038312

#	Time	Username	Problem	Language	Result	Execution time	Memory
1038312		Neco_arc	Constellation 3 (JOI20_constellation3)	C++17	100 / 100	208 ms	62812 KiB

constellation3

#include <bits/stdc++.h>
#ifdef LOCAL
#include <bits/debug.hpp>
#endif // LOCAL

#define ll long long
#define all(x) x.begin(), x.end()
#define Neco "Constellation 3"
#define resp(x) sort(all(x)), x.resize(unique(all(x)) - x.begin())
#define getbit(x,i) ((x >> i)&1)
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define cntbit(x) __builtin_popcountll(x)
#define fi(i, a, b) for(int i = a; i <= b; i++)
#define fid(i, a, b) for(int i = a; i >= b; i--)
#define maxn (int) 2e5 + 7

using namespace std;

const ll mod = 1e9 + 7; //972663749
const ll base = 911382323;

int n, m, rt;
int a[maxn];
vector<pair<int, int>> store[maxn];
int cha[maxn][18], ma[maxn][18];
int In[maxn], Out[maxn];
ll dp[maxn][2];
struct dl { int p, c[2]; } T[maxn];


struct BIT {
    ll bit[maxn];
    void update(int l, int r, ll val) {
        for(   l; l < maxn; l += (l & -l)) bit[l] += val;
        for(++ r; r < maxn; r += (r & -r)) bit[r] -= val;
    }
    ll get(int x, ll ans = 0) {
        for(; x > 0; x -= (x & -x)) ans += bit[x];
        return ans;
    }
} Bit;

void BuildTree() {
    a[0] = 1e9;
    fi(i, 1, n) {
        T[i].p = i - 1;
        while(a[i] > a[T[i].p]) T[i].p = T[T[i].p].p;

        T[i].c[0] = T[T[i].p].c[1];
        T[T[i].c[0]].p = i;

        T[T[i].p].c[1] = i;
    }
    fi(i, 1, n) if(T[i].p == 0) return rt = i, void();
}

void pre_dfs(int u) {
    static int Time = 0;
    In[u] = ++Time;
    for(int v : T[u].c) if(v != 0) {
        cha[v][0] = u, ma[v][0] = a[u];
        fi(i, 1, 17) {
            cha[v][i] = cha[cha[v][i - 1]][i - 1];
            ma[v][i] = max(ma[v][i - 1], ma[cha[v][i - 1]][i - 1]);
        }

        pre_dfs(v);
    }
    Out[u] = Time;
}

void Add(int x, int h, int val) {
    int u = x;
    fid(i, 17, 0) if(ma[u][i] < h) u = cha[u][i];
    store[u].push_back({x, val});
}

void dfs(int u) {
    for(int v : T[u].c) if(v != 0) {
        dfs(v);
        dp[u][0] += dp[v][1];
    }

    Bit.update(In[u], Out[u], dp[u][0]);
    dp[u][1] = dp[u][0];

    for(auto [v, w] : store[u]) dp[u][1] = max(dp[u][1], Bit.get(In[v]) + w);

    Bit.update(In[u], Out[u], -dp[u][1]);
}

void solve()
{

    cin >> n;
    fi(i, 1, n) cin >> a[i];

    BuildTree();

    memset(ma, 60, sizeof ma);
    pre_dfs(rt);

    cin >> m;

    ll S = 0;
    fi(i, 1, m) {
        int x, y, val; cin >> x >> y >> val;
        Add(x, y, val);
        S += val;
    }

    dfs(rt);
    cout << S - max(dp[rt][0], dp[rt][1]);

}


int main()
{

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

    if(fopen(Neco".inp", "r")) {
        freopen(Neco".inp", "r", stdin);
        freopen(Neco".out", "w", stdout);
    }


    int nTest = 1;
//    cin >> nTest;


    while(nTest--)
    {
        solve();
    }


    return 0;
}

Compilation message (stderr)

constellation3.cpp: In member function 'void BIT::update(int, int, long long int)':
constellation3.cpp:35:16: warning: statement has no effect [-Wunused-value]
   35 |         for(   l; l < maxn; l += (l & -l)) bit[l] += val;
      |                ^
constellation3.cpp: In function 'int main()':
constellation3.cpp:127:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  127 |         freopen(Neco".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
constellation3.cpp:128:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  128 |         freopen(Neco".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 21 / 21
• Subtask 3: 65 / 65