oj.uz

Submission #940496

# Submission time Handle Problem Language Result Execution time Memory
940496 2024-03-07T09:59:04 Z LucaIlie The short shank; Redemption (BOI21_prison) C++17
35 / 100
 2000 ms 115896 KB 
#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 2e6;
const long double INF = 1e15;
const long double eps = 1e-3;

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 = 1e6;
    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 4444 KB Output is correct
2 Correct 14 ms 4444 KB Output is correct
3 Correct 16 ms 4444 KB Output is correct
4 Correct 20 ms 4444 KB Output is correct
5 Correct 18 ms 4440 KB Output is correct
6 Correct 18 ms 4652 KB Output is correct
7 Correct 17 ms 4444 KB Output is correct
8 Correct 16 ms 4904 KB Output is correct
9 Correct 17 ms 4444 KB Output is correct
10 Correct 16 ms 4444 KB Output is correct
11 Correct 16 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 2082 ms 115896 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 4444 KB Output is correct
2 Correct 14 ms 4444 KB Output is correct
3 Correct 16 ms 4444 KB Output is correct
4 Correct 20 ms 4444 KB Output is correct
5 Correct 18 ms 4440 KB Output is correct
6 Correct 18 ms 4652 KB Output is correct
7 Correct 17 ms 4444 KB Output is correct
8 Correct 16 ms 4904 KB Output is correct
9 Correct 17 ms 4444 KB Output is correct
10 Correct 16 ms 4444 KB Output is correct
11 Correct 16 ms 4444 KB Output is correct
12 Correct 1 ms 4444 KB Output is correct
13 Correct 14 ms 4444 KB Output is correct
14 Correct 15 ms 4444 KB Output is correct
15 Correct 18 ms 4444 KB Output is correct
16 Correct 18 ms 4652 KB Output is correct
17 Correct 18 ms 4440 KB Output is correct
18 Correct 17 ms 4444 KB Output is correct
19 Correct 17 ms 4696 KB Output is correct
20 Correct 17 ms 4444 KB Output is correct
21 Correct 16 ms 4444 KB Output is correct
22 Correct 16 ms 4696 KB Output is correct
23 Correct 191 ms 5372 KB Output is correct
24 Correct 188 ms 5212 KB Output is correct
25 Correct 201 ms 5376 KB Output is correct
26 Correct 185 ms 5212 KB Output is correct
27 Correct 193 ms 5208 KB Output is correct
28 Correct 184 ms 5212 KB Output is correct
29 Correct 189 ms 5468 KB Output is correct
30 Correct 169 ms 5212 KB Output is correct
31 Correct 170 ms 5380 KB Output is correct
32 Correct 180 ms 5456 KB Output is correct
33 Correct 191 ms 5580 KB Output is correct
34 Correct 209 ms 5212 KB Output is correct
35 Correct 183 ms 5376 KB Output is correct

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Execution timed out 2082 ms 21036 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 4444 KB Output is correct
2 Correct 14 ms 4444 KB Output is correct
3 Correct 16 ms 4444 KB Output is correct
4 Correct 20 ms 4444 KB Output is correct
5 Correct 18 ms 4440 KB Output is correct
6 Correct 18 ms 4652 KB Output is correct
7 Correct 17 ms 4444 KB Output is correct
8 Correct 16 ms 4904 KB Output is correct
9 Correct 17 ms 4444 KB Output is correct
10 Correct 16 ms 4444 KB Output is correct
11 Correct 16 ms 4444 KB Output is correct
12 Correct 1 ms 4444 KB Output is correct
13 Correct 14 ms 4444 KB Output is correct
14 Correct 15 ms 4444 KB Output is correct
15 Correct 18 ms 4444 KB Output is correct
16 Correct 18 ms 4652 KB Output is correct
17 Correct 18 ms 4440 KB Output is correct
18 Correct 17 ms 4444 KB Output is correct
19 Correct 17 ms 4696 KB Output is correct
20 Correct 17 ms 4444 KB Output is correct
21 Correct 16 ms 4444 KB Output is correct
22 Correct 16 ms 4696 KB Output is correct
23 Correct 191 ms 5372 KB Output is correct
24 Correct 188 ms 5212 KB Output is correct
25 Correct 201 ms 5376 KB Output is correct
26 Correct 185 ms 5212 KB Output is correct
27 Correct 193 ms 5208 KB Output is correct
28 Correct 184 ms 5212 KB Output is correct
29 Correct 189 ms 5468 KB Output is correct
30 Correct 169 ms 5212 KB Output is correct
31 Correct 170 ms 5380 KB Output is correct
32 Correct 180 ms 5456 KB Output is correct
33 Correct 191 ms 5580 KB Output is correct
34 Correct 209 ms 5212 KB Output is correct
35 Correct 183 ms 5376 KB Output is correct
36 Correct 1 ms 4444 KB Output is correct
37 Execution timed out 2082 ms 21036 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 4444 KB Output is correct
2 Correct 14 ms 4444 KB Output is correct
3 Correct 16 ms 4444 KB Output is correct
4 Correct 20 ms 4444 KB Output is correct
5 Correct 18 ms 4440 KB Output is correct
6 Correct 18 ms 4652 KB Output is correct
7 Correct 17 ms 4444 KB Output is correct
8 Correct 16 ms 4904 KB Output is correct
9 Correct 17 ms 4444 KB Output is correct
10 Correct 16 ms 4444 KB Output is correct
11 Correct 16 ms 4444 KB Output is correct
12 Correct 1 ms 4444 KB Output is correct
13 Execution timed out 2082 ms 115896 KB Time limit exceeded
14 Halted 0 ms 0 KB -