oj.uz

Submission #940493

# Submission time Handle Problem Language Result Execution time Memory
940493 2024-03-07T09:56:54 Z LucaIlie The short shank; Redemption (BOI21_prison) C++17
35 / 100
 2000 ms 120452 KB 
#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 2e6;
const long double INF = 1e15;
const long double eps = 1e-15;

int groups[MAX_N + 1], firstLower[MAX_N + 1];
long long t[MAX_N + 1];
long double minPrisoners[MAX_N + 1];

struct info {
    long double minn;
    int pos;

    bool operator < ( const info &x ) const {
        return minn < x.minn;
    }
};

struct SegTree {
    int n, ls, rs;
    vector<info> segTree;
    vector<long double> lazy;

    void init( int v, int l, int r ) {
        lazy[v] = 0;
        if ( l == r ) {
            segTree[v] = { 0, l };
            return;
        }
        int mid = (l + r) / 2;
        init( v * 2 + 1, l, mid );
        init( v * 2 + 2, mid + 1, r );
        segTree[v] = min( segTree[v * 2 + 1], segTree[v * 2 + 2] );
    }

    void init( int _ls, int _rs ) {
        ls = _ls;
        rs = _rs;
        n = rs - ls + 1;
        segTree.resize( 4 * n );
        lazy.resize( 4 * n );
        init( 0, ls, rs );
    }

    void propag( int v, int l, int r ) {
        segTree[v].minn += lazy[v];
        if ( l != r ) {
            lazy[v * 2 + 1] += lazy[v];
            lazy[v * 2 + 2] += lazy[v];
        }
        lazy[v] = 0;
    }

    void update( int v, int l, int r, int lu, int ru, long double x ) {
        propag( v, l, r );

        if ( l > ru || r < lu )
            return;

        if ( lu <= l && r <= ru ) {
            lazy[v] += x;
            propag( v, l, r );
            return;
        }

        int mid = (l + r) / 2;
        update( v * 2 + 1, l, mid, lu, ru, x );
        update( v * 2 + 2, mid + 1, r, lu, ru, x );
        segTree[v] = min( segTree[v * 2 + 1], segTree[v * 2 + 2] );
    }

    void update( int l, int r, long double x ) {
        update( 0, ls, rs, l, r, x );
    }

    info query( int v, int l, int r, int lq, int rq ) {
        propag( v, l, r );

        if ( l > rq || r < lq )
            return { INF, 0 };

        if ( lq <= l && r <= rq )
            return segTree[v];

        int mid = (l + r) / 2;
        return min( query( v * 2 + 1, l, mid, lq, rq ), query( v * 2 + 2, mid + 1, r, lq, rq ) );
    }
} prisoners;

int main() {
    int n, d, s;

    cin >> n >> d >> s;
    d++;
    for ( int i = 1; i <= n; i++ ) {
        cin >> t[i];
        t[i] -= i;
    }
    t[0] = -INF;

    vector<int> stack;
    stack.push_back( 0 );
    for ( int i = 1; i <= n; i++ ) {
        while ( t[i] <= t[stack.back()] )
            stack.pop_back();
        stack.push_back( i );

        int l = 0, r = stack.size();
        while ( r - l > 1 ) {
            int mid = (l + r) / 2;

            if ( t[stack[mid]] <= s - i )
                l = mid;
            else
                r = mid;
        }
        firstLower[i] = stack[l];
    }


    cout << fixed << setprecision( 15 );
    long double lc = 0, rc = 100;
    while ( rc - lc > eps ) {
        long double cost = (rc + lc) / 2;

        prisoners.init( 1, n );
        for ( int i = 1; i <= n; i++ ) {
            prisoners.update( i, i, minPrisoners[i - 1] + cost );
            prisoners.update( 1, firstLower[i], 1 );

            auto x = prisoners.query( 0, 1, n, 1, i );
            minPrisoners[i] = x.minn;
            groups[i] = groups[x.pos - 1] + 1;
        }

        if ( groups[n] > d )
            lc = cost;
        else
            rc = cost;
    }
    long double cost = rc;
    prisoners.init( 1, n );
    for ( int i = 1; i <= n; i++ ) {
        prisoners.update( i, i, minPrisoners[i - 1] + cost );
        prisoners.update( 1, firstLower[i], 1 );

        auto x = prisoners.query( 0, 1, n, 1, i );
        minPrisoners[i] = x.minn;
        groups[i] = groups[x.pos] + 1;
    }

    long double ans = minPrisoners[n] - d * cost;
    if ( ceil( ans ) - ans < ans - floor( ans ) )
        cout << (int)ceil( ans );
    else
        cout << (int)floor( ans );

    return 0;
}

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4440 KB Output is correct
2 Correct 26 ms 4444 KB Output is correct
3 Correct 26 ms 4616 KB Output is correct
4 Correct 33 ms 4444 KB Output is correct
5 Correct 33 ms 4444 KB Output is correct
6 Correct 32 ms 4440 KB Output is correct
7 Correct 31 ms 4444 KB Output is correct
8 Correct 30 ms 4444 KB Output is correct
9 Correct 30 ms 4444 KB Output is correct
10 Correct 30 ms 4444 KB Output is correct
11 Correct 29 ms 4444 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Execution timed out 2092 ms 120452 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4440 KB Output is correct
2 Correct 26 ms 4444 KB Output is correct
3 Correct 26 ms 4616 KB Output is correct
4 Correct 33 ms 4444 KB Output is correct
5 Correct 33 ms 4444 KB Output is correct
6 Correct 32 ms 4440 KB Output is correct
7 Correct 31 ms 4444 KB Output is correct
8 Correct 30 ms 4444 KB Output is correct
9 Correct 30 ms 4444 KB Output is correct
10 Correct 30 ms 4444 KB Output is correct
11 Correct 29 ms 4444 KB Output is correct
12 Correct 1 ms 4440 KB Output is correct
13 Correct 26 ms 4444 KB Output is correct
14 Correct 26 ms 4444 KB Output is correct
15 Correct 32 ms 4444 KB Output is correct
16 Correct 32 ms 4444 KB Output is correct
17 Correct 33 ms 4440 KB Output is correct
18 Correct 33 ms 4440 KB Output is correct
19 Correct 32 ms 4444 KB Output is correct
20 Correct 30 ms 4444 KB Output is correct
21 Correct 30 ms 4632 KB Output is correct
22 Correct 29 ms 4444 KB Output is correct
23 Correct 343 ms 5416 KB Output is correct
24 Correct 358 ms 5456 KB Output is correct
25 Correct 345 ms 5416 KB Output is correct
26 Correct 343 ms 5208 KB Output is correct
27 Correct 342 ms 5420 KB Output is correct
28 Correct 345 ms 5636 KB Output is correct
29 Correct 344 ms 5208 KB Output is correct
30 Correct 305 ms 5576 KB Output is correct
31 Correct 307 ms 5460 KB Output is correct
32 Correct 336 ms 5456 KB Output is correct
33 Correct 325 ms 5396 KB Output is correct
34 Correct 350 ms 5396 KB Output is correct
35 Correct 343 ms 5400 KB Output is correct

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4440 KB Output is correct
2 Execution timed out 2080 ms 22224 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #5
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4440 KB Output is correct
2 Correct 26 ms 4444 KB Output is correct
3 Correct 26 ms 4616 KB Output is correct
4 Correct 33 ms 4444 KB Output is correct
5 Correct 33 ms 4444 KB Output is correct
6 Correct 32 ms 4440 KB Output is correct
7 Correct 31 ms 4444 KB Output is correct
8 Correct 30 ms 4444 KB Output is correct
9 Correct 30 ms 4444 KB Output is correct
10 Correct 30 ms 4444 KB Output is correct
11 Correct 29 ms 4444 KB Output is correct
12 Correct 1 ms 4440 KB Output is correct
13 Correct 26 ms 4444 KB Output is correct
14 Correct 26 ms 4444 KB Output is correct
15 Correct 32 ms 4444 KB Output is correct
16 Correct 32 ms 4444 KB Output is correct
17 Correct 33 ms 4440 KB Output is correct
18 Correct 33 ms 4440 KB Output is correct
19 Correct 32 ms 4444 KB Output is correct
20 Correct 30 ms 4444 KB Output is correct
21 Correct 30 ms 4632 KB Output is correct
22 Correct 29 ms 4444 KB Output is correct
23 Correct 343 ms 5416 KB Output is correct
24 Correct 358 ms 5456 KB Output is correct
25 Correct 345 ms 5416 KB Output is correct
26 Correct 343 ms 5208 KB Output is correct
27 Correct 342 ms 5420 KB Output is correct
28 Correct 345 ms 5636 KB Output is correct
29 Correct 344 ms 5208 KB Output is correct
30 Correct 305 ms 5576 KB Output is correct
31 Correct 307 ms 5460 KB Output is correct
32 Correct 336 ms 5456 KB Output is correct
33 Correct 325 ms 5396 KB Output is correct
34 Correct 350 ms 5396 KB Output is correct
35 Correct 343 ms 5400 KB Output is correct
36 Correct 1 ms 4440 KB Output is correct
37 Execution timed out 2080 ms 22224 KB Time limit exceeded
38 Halted 0 ms 0 KB -

Subtask #6
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4440 KB Output is correct
2 Correct 26 ms 4444 KB Output is correct
3 Correct 26 ms 4616 KB Output is correct
4 Correct 33 ms 4444 KB Output is correct
5 Correct 33 ms 4444 KB Output is correct
6 Correct 32 ms 4440 KB Output is correct
7 Correct 31 ms 4444 KB Output is correct
8 Correct 30 ms 4444 KB Output is correct
9 Correct 30 ms 4444 KB Output is correct
10 Correct 30 ms 4444 KB Output is correct
11 Correct 29 ms 4444 KB Output is correct
12 Correct 1 ms 4444 KB Output is correct
13 Execution timed out 2092 ms 120452 KB Time limit exceeded
14 Halted 0 ms 0 KB -