oj.uz

Submission #852122

# Submission time Handle Problem Language Result Execution time Memory
852122 2023-09-21T09:19:40 Z danikoynov Chorus (JOI23_chorus) C++14
87 / 100
 7000 ms 40572 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 ++)
    {
        while(dq.size() > 1)
        {
            int last = dq.back().first;
            if (get_better(last, i) < dq[dq.size() - 2].second)
            {
                dq.pop_back();
            }
            else
            {
                break;
            }
        }
        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 8536 KB Output is correct
6 Correct 1 ms 8536 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 2 ms 8536 KB Output is correct
9 Correct 1 ms 8540 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 8664 KB Output is correct
13 Correct 2 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 8536 KB Output is correct
6 Correct 1 ms 8536 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 2 ms 8536 KB Output is correct
9 Correct 1 ms 8540 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 8664 KB Output is correct
13 Correct 2 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 2 ms 8536 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 4 ms 8540 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 3 ms 8540 KB Output is correct
22 Correct 3 ms 8540 KB Output is correct
23 Correct 3 ms 8540 KB Output is correct
24 Correct 4 ms 8540 KB Output is correct
25 Correct 3 ms 8540 KB Output is correct
26 Correct 3 ms 8540 KB Output is correct
27 Correct 4 ms 8540 KB Output is correct
28 Correct 3 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 8536 KB Output is correct
6 Correct 1 ms 8536 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 2 ms 8536 KB Output is correct
9 Correct 1 ms 8540 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 8664 KB Output is correct
13 Correct 2 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 2 ms 8536 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 4 ms 8540 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 3 ms 8540 KB Output is correct
22 Correct 3 ms 8540 KB Output is correct
23 Correct 3 ms 8540 KB Output is correct
24 Correct 4 ms 8540 KB Output is correct
25 Correct 3 ms 8540 KB Output is correct
26 Correct 3 ms 8540 KB Output is correct
27 Correct 4 ms 8540 KB Output is correct
28 Correct 3 ms 8540 KB Output is correct
29 Correct 33 ms 8760 KB Output is correct
30 Correct 33 ms 8540 KB Output is correct
31 Correct 31 ms 8536 KB Output is correct
32 Correct 26 ms 8796 KB Output is correct
33 Correct 30 ms 8792 KB Output is correct
34 Correct 28 ms 8540 KB Output is correct
35 Correct 27 ms 8540 KB Output is correct
36 Correct 32 ms 8540 KB Output is correct
37 Correct 32 ms 8552 KB Output is correct
38 Correct 27 ms 8536 KB Output is correct
39 Correct 30 ms 8540 KB Output is correct
40 Correct 27 ms 8540 KB Output is correct
41 Correct 31 ms 8540 KB Output is correct
42 Correct 21 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 8536 KB Output is correct
6 Correct 1 ms 8536 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 2 ms 8536 KB Output is correct
9 Correct 1 ms 8540 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 8664 KB Output is correct
13 Correct 2 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 2 ms 8536 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 4 ms 8540 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 3 ms 8540 KB Output is correct
22 Correct 3 ms 8540 KB Output is correct
23 Correct 3 ms 8540 KB Output is correct
24 Correct 4 ms 8540 KB Output is correct
25 Correct 3 ms 8540 KB Output is correct
26 Correct 3 ms 8540 KB Output is correct
27 Correct 4 ms 8540 KB Output is correct
28 Correct 3 ms 8540 KB Output is correct
29 Correct 33 ms 8760 KB Output is correct
30 Correct 33 ms 8540 KB Output is correct
31 Correct 31 ms 8536 KB Output is correct
32 Correct 26 ms 8796 KB Output is correct
33 Correct 30 ms 8792 KB Output is correct
34 Correct 28 ms 8540 KB Output is correct
35 Correct 27 ms 8540 KB Output is correct
36 Correct 32 ms 8540 KB Output is correct
37 Correct 32 ms 8552 KB Output is correct
38 Correct 27 ms 8536 KB Output is correct
39 Correct 30 ms 8540 KB Output is correct
40 Correct 27 ms 8540 KB Output is correct
41 Correct 31 ms 8540 KB Output is correct
42 Correct 21 ms 8796 KB Output is correct
43 Correct 553 ms 11864 KB Output is correct
44 Correct 964 ms 14156 KB Output is correct
45 Correct 925 ms 14152 KB Output is correct
46 Correct 836 ms 14572 KB Output is correct
47 Correct 929 ms 14160 KB Output is correct
48 Correct 863 ms 14352 KB Output is correct
49 Correct 838 ms 14164 KB Output is correct
50 Correct 1079 ms 14152 KB Output is correct
51 Correct 1057 ms 14340 KB Output is correct
52 Correct 847 ms 14336 KB Output is correct
53 Correct 865 ms 14212 KB Output is correct
54 Correct 1028 ms 14152 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 8536 KB Output is correct
6 Correct 1 ms 8536 KB Output is correct
7 Correct 1 ms 8540 KB Output is correct
8 Correct 2 ms 8536 KB Output is correct
9 Correct 1 ms 8540 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 8664 KB Output is correct
13 Correct 2 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 2 ms 8536 KB Output is correct
18 Correct 3 ms 8540 KB Output is correct
19 Correct 4 ms 8540 KB Output is correct
20 Correct 2 ms 8540 KB Output is correct
21 Correct 3 ms 8540 KB Output is correct
22 Correct 3 ms 8540 KB Output is correct
23 Correct 3 ms 8540 KB Output is correct
24 Correct 4 ms 8540 KB Output is correct
25 Correct 3 ms 8540 KB Output is correct
26 Correct 3 ms 8540 KB Output is correct
27 Correct 4 ms 8540 KB Output is correct
28 Correct 3 ms 8540 KB Output is correct
29 Correct 33 ms 8760 KB Output is correct
30 Correct 33 ms 8540 KB Output is correct
31 Correct 31 ms 8536 KB Output is correct
32 Correct 26 ms 8796 KB Output is correct
33 Correct 30 ms 8792 KB Output is correct
34 Correct 28 ms 8540 KB Output is correct
35 Correct 27 ms 8540 KB Output is correct
36 Correct 32 ms 8540 KB Output is correct
37 Correct 32 ms 8552 KB Output is correct
38 Correct 27 ms 8536 KB Output is correct
39 Correct 30 ms 8540 KB Output is correct
40 Correct 27 ms 8540 KB Output is correct
41 Correct 31 ms 8540 KB Output is correct
42 Correct 21 ms 8796 KB Output is correct
43 Correct 553 ms 11864 KB Output is correct
44 Correct 964 ms 14156 KB Output is correct
45 Correct 925 ms 14152 KB Output is correct
46 Correct 836 ms 14572 KB Output is correct
47 Correct 929 ms 14160 KB Output is correct
48 Correct 863 ms 14352 KB Output is correct
49 Correct 838 ms 14164 KB Output is correct
50 Correct 1079 ms 14152 KB Output is correct
51 Correct 1057 ms 14340 KB Output is correct
52 Correct 847 ms 14336 KB Output is correct
53 Correct 865 ms 14212 KB Output is correct
54 Correct 1028 ms 14152 KB Output is correct
55 Execution timed out 7042 ms 40572 KB Time limit exceeded
56 Halted 0 ms 0 KB -