oj.uz

Submission #852124

# Submission time Handle Problem Language Result Execution time Memory
852124 2023-09-21T09:21:20 Z danikoynov Chorus (JOI23_chorus) C++14
87 / 100
 7000 ms 51540 KB 
/**
 ____ ____ ____ ____ ____ ____
||l |||e |||i |||n |||a |||d ||
||__|||__|||__|||__|||__|||__||
|/__\|/__\|/__\|/__\|/__\|/__\|

**/

#include<bits/stdc++.h>
#define endl '\n'

using namespace std;
typedef long long ll;

void speed()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}

const ll maxn = 1e6 + 10;
const ll inf = 1e18;

ll n, k;
string s;

ll pos[2][maxn], pref[maxn];
/// ll dp[maxn][maxn];
/**

*/

void chmin(ll &var, ll val) /// careful for long long
{
    var = min(var, val);
}

int pre_cost[maxn];

void precompute()
{
    for (int i = 1; i <= n; i ++)
    {
        int above = (i - 1) * 2;
        int lf = i, rf = n;
        while(lf <= rf)
        {
            int mf = (lf + rf) / 2;
            if (pos[0][mf] > above + (mf - i + 1))
                rf = mf - 1;
            else
                lf = mf + 1;
        }
        pre_cost[i] = lf;
    }
}
ll cost(ll left, ll right)
{
    if (pre_cost[left] > right)
        return 0;

        ll lf = pre_cost[left];
    ll above = (left - 1) * 2;

    ll sum = pref[right] - pref[lf - 1];
    sum = sum - (right - lf + 1) * above;
    ll len = right - left + 1;
    ll sm = lf - left;
    sum = sum - (len) * (len + 1) / 2;
    sum = sum + (sm) * (sm + 1) / 2;

    return sum;

}

/**void divide(ll row, ll left, ll right, ll optl, ll optr)
{
    if (left > right)
        return;

    ll mid = (left + right) / 2;
    ll opt = -1;
    for (ll j = optl; j <= min(optr, mid); j ++)
    {
        ll cur = dp[j - 1][row - 1] + costd[j][mid];
        if (cur < dp[mid][row])
        {
            dp[mid][row] = cur;
            opt = j;
        }
    }

    divide(row, left, mid - 1, optl, opt);
    divide(row, mid + 1, right, opt, optr);
}*/



ll dp[maxn], f[maxn];

ll get_better(int i, int j)
{
    int lf = 1, rf = n;
    while(lf <= rf)
    {
        int mf = (lf + rf) / 2;
        if (dp[i - 1] + cost(i, mf) > dp[j - 1] + cost(j, mf))
            rf = mf - 1;
        else
            lf = mf + 1;
    }

    return lf;
}
pair < ll, ll > calc_dp(ll group_cost)
{
    for (int i = 1; i <= n; i ++)
    {
        dp[i] = inf;
        f[i] = 0;
    }
    deque < pair < int, int > > dq;
    for (int i = 1; i <= n; i ++)
    {
        int sv = -1;
        while(dq.size() > 1)
        {
            int last = dq.back().first;
            sv = get_better(last, i);
            if (sv < dq[dq.size() - 2].second)
            {
                dq.pop_back();
            }
            else
            {
                break;
            }
        }
        if (dq.size() > 1)
            dq.back().second = sv;
        else
        if (!dq.empty())
            dq.back().second = get_better(dq.back().first, i);
        dq.push_back({i, 0});

        while(dq.size() > 1)
        {
            if (dq[0].second <= i)
                dq.pop_front();
            else
                break;
        }

        dp[i] = dp[dq[0].first - 1] + cost(dq[0].first, i) + group_cost;
        f[i] = f[dq[0].first - 1] + 1;

        /**for (int j = 1; j <= i; j ++)
        {
            ll cur = dp[j - 1] + cost(j, i) + group_cost;
            if (cur < dp[i])
            {
                dp[i] = cur;
                f[i] = f[j - 1] + 1;
            }
        }*/
    }


    return {dp[n], f[n]};
}
void solve()
{
    cin >> n >> k >> s;

    s = "#" + s;
    ll cntA = 0, cntB = 0;
    for (ll i = 1; i <= 2 * n; i ++)
    {
        if (s[i] == 'A')
        {
            cntA ++;
            pos[0][cntA] = i;
            pref[cntA] = pref[cntA - 1] + i;
        }
        else
        {
            cntB ++;
            pos[1][cntB] = i;
        }
    }

    ///for (ll i = 0; i <= n; i ++)
       // for (ll j = 0; j <= n; j ++)
         //   dp[i][j] = 4 * n * n; /// careful for overflow

    /**ll cr = 0;
    for (ll j = 1; j <= n; j ++)
    {
        cr = cr + pos[0][j] - j;

        dp[j][1] = cr;
    }

    for (ll j = 2; j <= k; j ++)

    {
        divide(j, j, n, j, n);
    }*/

    precompute();
    ll lf = 0, rf = n * n / 2;
    while(lf <= rf)
    {
        ll mf = (lf + rf) / 2;
        pair < ll, ll > cur = calc_dp(mf);
        if (cur.second <= k)
            rf = mf - 1;
        else
            lf = mf + 1;
    }

    if (rf < 0)
    {
        pair < ll, ll > cur = calc_dp(0);
        cout << cur.first << endl;
        return;
    }
    pair < ll, ll > fs = calc_dp(rf);
    pair < ll, ll > ds = calc_dp(rf + 1);

    ll fs_val = fs.first - fs.second * rf;
    ll ds_val = ds.first - ds.second * (rf + 1);

    double part = (double)(fs.second - k) / (double)(fs.second - ds.second); /// remember to cast
    double ans = (double)(fs_val) + part * (double)(ds_val - fs_val);
    ///cout << ds.first << "  " << ds.second << endl;
    ///cout << fs.first << "  " << fs.second << endl;
    cout << (ll)(round(ans)) << endl;
}

int main()
{
    speed();
    ///freopen("test.txt", "r", stdin);
    solve();
    return 0;
}

Compilation message

chorus.cpp: In function 'll cost(ll, ll)':
chorus.cpp:60:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   60 |     if (pre_cost[left] > right)
      |     ^~
chorus.cpp:63:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   63 |         ll lf = pre_cost[left];
      |         ^~

Subtask #1
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8540 KB Output is correct
5 Correct 1 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 1 ms 8792 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 1 ms 8540 KB Output is correct
12 Correct 1 ms 8536 KB Output is correct
13 Correct 1 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 1 ms 8540 KB Output is correct
16 Correct 1 ms 8540 KB Output is correct

Subtask #2
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8540 KB Output is correct
5 Correct 1 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 1 ms 8792 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 1 ms 8540 KB Output is correct
12 Correct 1 ms 8536 KB Output is correct
13 Correct 1 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 1 ms 8540 KB Output is correct
16 Correct 1 ms 8540 KB Output is correct
17 Correct 1 ms 8540 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 2 ms 8672 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 2 ms 8540 KB Output is correct
22 Correct 2 ms 8540 KB Output is correct
23 Correct 2 ms 8540 KB Output is correct
24 Correct 2 ms 8540 KB Output is correct
25 Correct 2 ms 8540 KB Output is correct
26 Correct 2 ms 8540 KB Output is correct
27 Correct 2 ms 8540 KB Output is correct
28 Correct 2 ms 8540 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8540 KB Output is correct
5 Correct 1 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 1 ms 8792 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 1 ms 8540 KB Output is correct
12 Correct 1 ms 8536 KB Output is correct
13 Correct 1 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 1 ms 8540 KB Output is correct
16 Correct 1 ms 8540 KB Output is correct
17 Correct 1 ms 8540 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 2 ms 8672 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 2 ms 8540 KB Output is correct
22 Correct 2 ms 8540 KB Output is correct
23 Correct 2 ms 8540 KB Output is correct
24 Correct 2 ms 8540 KB Output is correct
25 Correct 2 ms 8540 KB Output is correct
26 Correct 2 ms 8540 KB Output is correct
27 Correct 2 ms 8540 KB Output is correct
28 Correct 2 ms 8540 KB Output is correct
29 Correct 19 ms 8540 KB Output is correct
30 Correct 20 ms 8792 KB Output is correct
31 Correct 20 ms 8540 KB Output is correct
32 Correct 21 ms 8796 KB Output is correct
33 Correct 21 ms 8796 KB Output is correct
34 Correct 17 ms 8796 KB Output is correct
35 Correct 17 ms 8796 KB Output is correct
36 Correct 22 ms 8772 KB Output is correct
37 Correct 21 ms 8540 KB Output is correct
38 Correct 18 ms 8796 KB Output is correct
39 Correct 20 ms 8792 KB Output is correct
40 Correct 19 ms 8540 KB Output is correct
41 Correct 20 ms 8796 KB Output is correct
42 Correct 14 ms 8796 KB Output is correct

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8540 KB Output is correct
5 Correct 1 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 1 ms 8792 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 1 ms 8540 KB Output is correct
12 Correct 1 ms 8536 KB Output is correct
13 Correct 1 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 1 ms 8540 KB Output is correct
16 Correct 1 ms 8540 KB Output is correct
17 Correct 1 ms 8540 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 2 ms 8672 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 2 ms 8540 KB Output is correct
22 Correct 2 ms 8540 KB Output is correct
23 Correct 2 ms 8540 KB Output is correct
24 Correct 2 ms 8540 KB Output is correct
25 Correct 2 ms 8540 KB Output is correct
26 Correct 2 ms 8540 KB Output is correct
27 Correct 2 ms 8540 KB Output is correct
28 Correct 2 ms 8540 KB Output is correct
29 Correct 19 ms 8540 KB Output is correct
30 Correct 20 ms 8792 KB Output is correct
31 Correct 20 ms 8540 KB Output is correct
32 Correct 21 ms 8796 KB Output is correct
33 Correct 21 ms 8796 KB Output is correct
34 Correct 17 ms 8796 KB Output is correct
35 Correct 17 ms 8796 KB Output is correct
36 Correct 22 ms 8772 KB Output is correct
37 Correct 21 ms 8540 KB Output is correct
38 Correct 18 ms 8796 KB Output is correct
39 Correct 20 ms 8792 KB Output is correct
40 Correct 19 ms 8540 KB Output is correct
41 Correct 20 ms 8796 KB Output is correct
42 Correct 14 ms 8796 KB Output is correct
43 Correct 333 ms 11672 KB Output is correct
44 Correct 611 ms 14152 KB Output is correct
45 Correct 595 ms 14160 KB Output is correct
46 Correct 664 ms 14372 KB Output is correct
47 Correct 672 ms 14616 KB Output is correct
48 Correct 515 ms 14116 KB Output is correct
49 Correct 512 ms 14164 KB Output is correct
50 Correct 714 ms 14156 KB Output is correct
51 Correct 687 ms 14344 KB Output is correct
52 Correct 539 ms 14332 KB Output is correct
53 Correct 515 ms 14344 KB Output is correct
54 Correct 647 ms 14168 KB Output is correct

Subtask #5
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 8540 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8540 KB Output is correct
5 Correct 1 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 1 ms 8792 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 1 ms 8540 KB Output is correct
12 Correct 1 ms 8536 KB Output is correct
13 Correct 1 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 1 ms 8540 KB Output is correct
16 Correct 1 ms 8540 KB Output is correct
17 Correct 1 ms 8540 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 2 ms 8672 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 2 ms 8540 KB Output is correct
22 Correct 2 ms 8540 KB Output is correct
23 Correct 2 ms 8540 KB Output is correct
24 Correct 2 ms 8540 KB Output is correct
25 Correct 2 ms 8540 KB Output is correct
26 Correct 2 ms 8540 KB Output is correct
27 Correct 2 ms 8540 KB Output is correct
28 Correct 2 ms 8540 KB Output is correct
29 Correct 19 ms 8540 KB Output is correct
30 Correct 20 ms 8792 KB Output is correct
31 Correct 20 ms 8540 KB Output is correct
32 Correct 21 ms 8796 KB Output is correct
33 Correct 21 ms 8796 KB Output is correct
34 Correct 17 ms 8796 KB Output is correct
35 Correct 17 ms 8796 KB Output is correct
36 Correct 22 ms 8772 KB Output is correct
37 Correct 21 ms 8540 KB Output is correct
38 Correct 18 ms 8796 KB Output is correct
39 Correct 20 ms 8792 KB Output is correct
40 Correct 19 ms 8540 KB Output is correct
41 Correct 20 ms 8796 KB Output is correct
42 Correct 14 ms 8796 KB Output is correct
43 Correct 333 ms 11672 KB Output is correct
44 Correct 611 ms 14152 KB Output is correct
45 Correct 595 ms 14160 KB Output is correct
46 Correct 664 ms 14372 KB Output is correct
47 Correct 672 ms 14616 KB Output is correct
48 Correct 515 ms 14116 KB Output is correct
49 Correct 512 ms 14164 KB Output is correct
50 Correct 714 ms 14156 KB Output is correct
51 Correct 687 ms 14344 KB Output is correct
52 Correct 539 ms 14332 KB Output is correct
53 Correct 515 ms 14344 KB Output is correct
54 Correct 647 ms 14168 KB Output is correct
55 Correct 5018 ms 40328 KB Output is correct
56 Execution timed out 7013 ms 51540 KB Time limit exceeded
57 Halted 0 ms 0 KB -