Submission #1138103

#	Time	Username	Problem	Language	Result	Execution time	Memory
1138103		VMaksimoski008	Cat Exercise (JOI23_ho_t4)	C++20	41 / 100	129 ms	37004 KiB

Main

#include <bits/stdc++.h>
#define ar array
//#define int long long

using namespace std;

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

const int mod = 1e9 + 7;
const int LOG = 20;
const int maxn = 2e5 + 5;

int n, P[maxn], T[maxn][20];
vector<int> G[maxn];

int mrg(int i, int j) {
    return P[i] > P[j] ? i : j;
}

int query(int l, int r) {
    int k = __lg(r-l+1);
    return mrg(T[l][k], T[r-(1<<k)+1][k]);
}

ll dnc(int l, int r, int p) {
    if(l == r) return 0;
    ll ans = 0;

    //oj levo
    if(p > l) {
        int p2 = query(l, p-1);
        ans = max(ans, p - p2 + dnc(l, p-1, p2));
    }

    //oj desno
    if(p < r) {
        int p2 = query(p+1, r);
        ans = max(ans, p2 - p + dnc(p+1, r, p2));
    }

    return ans;
}

signed main() {
    cin >> n;
    for(int i=1; i<=n; i++) cin >> P[i];
    for(int i=1; i<=n; i++) T[i][0] = i;

    for(int j=1; j<20; j++)
        for(int i=1; i+(1<<j)-1<=n; i++) T[i][j] = mrg(T[i][j-1], T[i+(1<<(j-1))][j-1]);

    for(int i=0; i<n-1; i++) {
        int a, b; cin >> a >> b;
        G[a].push_back(b);
        G[b].push_back(a);
    }

    cout << dnc(1, n, query(1, n)) << '\n';
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 7 / 7
• Subtask 4: 0 / 10
• Subtask 5: 20 / 20
• Subtask 6: 0 / 23
• Subtask 7: 0 / 26