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Submission #815551

# Submission time Handle Problem Language Result Execution time Memory
815551 2023-08-08T16:52:03 Z VMaksimoski008 Exam (eJOI20_exam) C++14
77 / 100
 140 ms 197068 KB 
#include <bits/stdc++.h>

#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define uniq(x) x.erase(unique(all(x)), x.end())
#define rall(x) x.rbegin(), x.rend()
#define each(x, v) for(auto &x : v)
#define mp make_pair

using namespace std;

using ll = long long;
using ull = unsigned long long;
using ld = long double;
using str = string;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

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

void setIO() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
}

int n;
vector<int> a, b;
vector<int> L, R;

void solve_2() {
    int curr = b[0];
    int ans = 0;

    for(int i=0; i<n; i++) {
        if(a[i] != curr) continue;
        ans++;
        int j = i-1;
        while(j >= 0 && a[j] <= curr) j--, ans++;
        j = i+1;
        while(j < n && a[j] <= curr) j++, ans++;
        i = j-1;
    }

    cout << ans << '\n';
}

struct SegTree {
    int n;
    vector<int> tree;

    SegTree(int n) : n(n), tree(4*n+5, 0) {}

    void update(int u, int tl, int tr, int pos, int val) {
        if(tl == tr) {
            tree[u] = val;
        } else {
            int tm = (tl + tr) / 2;
            if(tm <= pos)
                update(2*u, tl, tm, pos, val);
            else
                update(2*u, tm+1, tr, pos, val);
            tree[u] = max(tree[2*u], tree[2*u+1]);
        }
    }

    int query(int u, int tl, int tr, int l, int r) {
        if(tl > tr || l > tr || tl > r) return 0;
        if(l <= tl && tr <= r) return tree[u];
        int tm = (tl + tr) / 2;
        return max(
          query(2*u, tl, tm, l, r),
          query(2*u+1, tm+1, tr, l, r)  
        );
    }

    void update(int pos, int val) {
        update(1, 0, n-1, pos, val);
    }

    int query(int l, int r) {
        return query(1, 0, n-1, l, r);
    }
};

int32_t main() {
    setIO();

    cin >> n;
    a.resize(n);
    b.resize(n);
    L.resize(n);
    R.resize(n);
    vector<int> temp(n+2, 0);
    set<int> diff;
    map<int, int> comp;

    int id = 1;
    for(int &x : a) cin >> x, comp[x] = id - 1, temp[id++] = x;
    for(int &x : b) cin >> x, diff.insert(x);

    if(sz(diff) == 1) {
        solve_2();
        return 0;
    }

    temp[0] = INT_MAX;
    temp[n+1] = temp[0];

    stack<int> st;
    st.push(0);

    for(int i=1; i<=n; i++) {
        while(temp[st.top()] <= temp[i])
            st.pop();
        L[i-1] = st.top() - 1;
        st.push(i);
    }

    while(!st.empty()) st.pop();

    st.push(n+1);
    for(int i=n; i>=1; i--) {
        while(temp[st.top()] <= temp[i])
            st.pop();
        R[i-1] = st.top() - 1;
        st.push(i);
    }
    
    if(n <= 5000) {
        vector<vector<ll> > dp(n+5, vector<ll>(n+5, 0));
        for(int i=1; i<=n; i++) {
            for(int j=1; j<=n; j++) {
                if(a[i-1] == b[j-1] && L[i-1] < j-1 && j-1 < R[i-1])
                    dp[i][j] = dp[i][j-1] + 1;
                dp[i][j] = max(dp[i][j], dp[i-1][j]);
                dp[i][j] = max(dp[i][j], dp[i][j-1]);
            }
        }

        cout << dp[n][n] << '\n';
        return 0;
    }

    SegTree tree(n+1);

    for(int i=0; i<n; i++) {
        int ans = 0;
        if(comp.find(b[i]) == comp.end()) continue;
        if(L[comp[b[i]]] < i && R[comp[b[i]]] > i) {
            ans = tree.query(0, comp[b[i]]);
            tree.update(comp[b[i]], ans+1);
        }
    }

    cout << tree.query(0, n-1) << '\n';
    return 0;
}

Subtask #1
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 4 ms 596 KB Output is correct
3 Correct 26 ms 6196 KB Output is correct
4 Correct 9 ms 2260 KB Output is correct
5 Correct 45 ms 6936 KB Output is correct
6 Correct 11 ms 2296 KB Output is correct
7 Correct 12 ms 2260 KB Output is correct
8 Correct 41 ms 5196 KB Output is correct

Subtask #3
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 2260 KB Output is correct
3 Correct 18 ms 32016 KB Output is correct
4 Correct 90 ms 181656 KB Output is correct
5 Correct 97 ms 197068 KB Output is correct
6 Correct 106 ms 196972 KB Output is correct

Subtask #4
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 4 ms 852 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 596 KB Output is correct
11 Correct 1 ms 596 KB Output is correct
12 Correct 1 ms 596 KB Output is correct
13 Correct 1 ms 596 KB Output is correct
14 Correct 1 ms 596 KB Output is correct

Subtask #6
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 2 ms 2260 KB Output is correct
9 Correct 18 ms 32016 KB Output is correct
10 Correct 90 ms 181656 KB Output is correct
11 Correct 97 ms 197068 KB Output is correct
12 Correct 106 ms 196972 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 596 KB Output is correct
17 Correct 1 ms 596 KB Output is correct
18 Correct 1 ms 596 KB Output is correct
19 Correct 1 ms 596 KB Output is correct
20 Correct 1 ms 596 KB Output is correct
21 Correct 0 ms 596 KB Output is correct
22 Correct 5 ms 8276 KB Output is correct
23 Correct 1 ms 340 KB Output is correct
24 Correct 140 ms 196600 KB Output is correct
25 Correct 124 ms 196680 KB Output is correct
26 Correct 103 ms 196700 KB Output is correct
27 Correct 107 ms 196636 KB Output is correct
28 Correct 104 ms 196976 KB Output is correct
29 Correct 97 ms 196944 KB Output is correct
30 Correct 102 ms 196956 KB Output is correct
31 Correct 105 ms 197052 KB Output is correct
32 Correct 103 ms 196868 KB Output is correct