Submission #1032548

#	Time	Username	Problem	Language	Result	Execution time	Memory
1032548		HorizonWest	The short shank; Redemption (BOI21_prison)	C++17	55 / 100	342 ms	524288 KiB

prison

#include <bits/stdc++.h>
using namespace std;

#pragma GCC optimize("O3")
#define endl '\n'
#define db double
#define ll __int128
#define int long long
#define pb push_back
#define fs first
#define sd second
#define Mod long(1e9 + 7)
#define all(x) x.begin(), x.end()
#define unvisited long(-1)
#define Eps double(1e-9)
#define _for(i, n) for(int i = 0; i < (n); i++)
#define dbg(x) cout << #x ": " << x << endl;

const int Max = 1e6 + 7, Inf = 1e9 + 7;

void print(bool x) { cout << (x ? "YES" : "NO") << endl; }

string tostring (__int128 x)
{
    string ans = "";
    while(x > 0)
    {
        ans += (x % 10 + '0');
        x /= 10;
    }
    reverse(all(ans));
    return ans;
}

struct SegmentTreeLazy
{
    struct node
    {
        int value, lazy;

        node(int v = 0)
        {
            value = v;
            lazy = 0;
        }
    };

    vector <node> tree; int l;

    void update(int v, int s, int e, int k)
    {
        tree[v].lazy += k;
        tree[v].value += k;
    }

    void push(int v, int s, int e)
    {
        if (tree[v].lazy)
        {
            int middle = (s + e) / 2;

            update(2 * v, s, middle, tree[v].lazy);
            update(2 * v + 1, middle + 1, e, tree[v].lazy);

            tree[v].lazy = 0;
        }
    }

    void increase(int node, int v, int x, int y, int s, int e)
    {
        if (s > y || e < x) return;

        if (s >= x && e <= y)
        {
            update(node, s, e, v);
            return;
        }

        push(node, s, e);

        int middle = (s + e) / 2;

        increase(node * 2, v, x, y, s, middle);
        increase(node * 2 + 1, v, x, y, middle + 1, e);

        tree[node].value = max(tree[node * 2].value,
            tree[node * 2 + 1].value);
    }

    void increase(int x, int y, int k) { increase(1, k, x+1, y+1, 1, l); }

    int sum(int node, int x, int y, int s, int e)
    {
        if (s > y || e < x) return 0;

        if (s >= x && e <= y)
            return tree[node].value;

        push(node, s, e);
        int middle = (s + e) / 2;

        return max(sum(node * 2, x, y, s, middle),
            sum(node * 2 + 1, x, y, middle + 1, e));
    }

    int query(int x, int y) { return sum(1, x+1, y+1, 1, l); }

    SegmentTreeLazy(int n)
    {
        for (l = 1; l < n; l = (l << 1));
        tree.resize(2 * l);
    }
};

void solve()
{
    int n, d, t; cin >> n >> d >> t; 
    vector <int> v(n), c(n, -1); 
    for(auto& u : v) cin >> u; 

    stack <int> q; 
    for(int i = n-1; i >= 0; i--)
    {
        if(v[i] > t){
            q.push(i); 
            continue;
        }

        while (!q.empty())
        {
            int x = q.top();
            if(abs(t-v[i]) >= abs(x-i)){
                c[x] = i; 
                q.pop(); 
            } else break;
        }
    }  
    
    vector <SegmentTreeLazy> dp(d+1, SegmentTreeLazy(n+1));

    auto f = [&](int i, int j) {
        if(c[i] == -1) return 0LL; 
        return ((int) (c[i] <= j && j < i)); 
    };

    int ans = 0;    

    for(int i = 0; i < n; i++)
    {
        for(int k = 1; k <= d; k++){
            if(c[i] != -1) {
                dp[k].increase(c[i], i-1, 1); 
            }
            dp[k].increase(i, i, dp[k-1].query(0, i)); 
        }
    }

    ans = dp[d].query(0, n-1); 

    cout << (n - (ans + q.size())) << endl; 
}

int32_t main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int Q = 1; //cin >> Q;

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

    return 0;
}

Compilation message (stderr)

prison.cpp: In function 'void solve()':
prison.cpp:141:10: warning: variable 'f' set but not used [-Wunused-but-set-variable]
  141 |     auto f = [&](int i, int j) {
      |          ^

• Subtask 1: 15 / 15
• Subtask 2: 10 / 10
• Subtask 3: 20 / 20
• Subtask 4: 10 / 10
• Subtask 5: 0 / 25
• Subtask 6: 0 / 20