답안 #934477

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
934477	2024-02-27T11:50:13 Z	boris_mihov	Chorus (JOI23_chorus)	C++17	61 / 100	7000 ms	9236 KB

chorus

#include <algorithm>
#include <iostream>
#include <numeric>
#include <cassert>
#include <vector>

typedef long long llong;
const int MAXN = 1000000 + 10;
const llong INF = 1e18;

int n, k;
struct ConvexHullTrick
{

};

int h[MAXN];
int next[MAXN];
llong prefix[MAXN];
std::pair <llong,int> dp[MAXN];
char s[2 * MAXN];

llong cost(int l, int r)
{
    return prefix[r] - (r + 1) * (l - 1);
}

std::pair <llong,int> calc(llong penalty)
{
    dp[n + 1] = {0, 0};
    for (int pos = n ; pos >= 1 ; --pos)
    {
        dp[pos] = {INF, 0};
        if (pos < next[pos])
        {
            dp[pos] = dp[next[pos]];
            dp[pos].first += penalty;
            dp[pos].second++;
        }

        llong addedValue = (next[pos] - pos + 1) * (pos - 1) + pos * (pos - 1) - prefix[next[pos]] + penalty;
        for (int nextPos = next[pos] + 1 ; nextPos <= n + 1 ; ++nextPos)
        {
            std::pair <llong,int> res = dp[nextPos];
            res.first += addedValue + cost(pos, nextPos - 1);
            res.second += 1;

            dp[pos] = std::min(dp[pos], res);
        }
    }

    return dp[1];
}

void solve()
{
    int cntA = 0;
    int cntB = 0;
    for (int i = 1 ; i <= 2 * n ; ++i)
    {
        if (s[i] == 'B')
        {
            cntB++;
        } else
        {
            cntA++;
            h[cntA] = cntB;
        }
    }

    for (int i = 1 ; i <= n ; ++i)
    {
        prefix[i] = prefix[i - 1] + h[i];
    }

    next[n + 1] = n + 1;
    h[n + 1] = n + 1;
    for (int i = n ; i >= 1 ; --i)
    {
        next[i] = next[i + 1];
        while (next[i] >= i && h[next[i]] >= i)
        {
            next[i]--;
        }
    }

    llong l = -1, r = 1LL * n * n + 1, mid;
    while (l < r - 1)
    {
        mid = (l + r) / 2;
        if (calc(mid).second > k) l = mid;
        else r = mid;
    }

    auto [fL, groupsL] = calc(l);
    auto [fR, groupsR] = calc(r); 
    fL -= groupsL * l;
    fR -= groupsR * r;

    if (groupsR == k)
    {
        std::cout << fR << '\n';
        return;
    }

    std::cout << fL + (fR - fL) * (groupsL - k) / (groupsL - groupsR) << '\n';
}

void input()
{
    std::cin >> n >> k;
    std::cin >> s + 1;
}

void fastIOI()
{
    std::ios_base :: sync_with_stdio(0);
    std::cout.tie(nullptr);
    std::cin.tie(nullptr);
}

int main()
{
    fastIOI();
    input();
    solve();

    return 0;
}

Compilation message

chorus.cpp: In function 'void input()':
chorus.cpp:112:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  112 |     std::cin >> s + 1;
      |                 ~~^~~

Subtask #1

16.0 / 16.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6488 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	1 ms	6492 KB	Output is correct
4	Correct	1 ms	6608 KB	Output is correct
5	Correct	1 ms	6488 KB	Output is correct
6	Correct	1 ms	6492 KB	Output is correct
7	Correct	1 ms	6492 KB	Output is correct
8	Correct	1 ms	6492 KB	Output is correct
9	Correct	1 ms	6492 KB	Output is correct
10	Correct	1 ms	6492 KB	Output is correct
11	Correct	1 ms	6604 KB	Output is correct
12	Correct	1 ms	6492 KB	Output is correct
13	Correct	1 ms	6604 KB	Output is correct
14	Correct	2 ms	6492 KB	Output is correct
15	Correct	1 ms	6488 KB	Output is correct
16	Correct	1 ms	6492 KB	Output is correct

Subtask #2

24.0 / 24.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6488 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	1 ms	6492 KB	Output is correct
4	Correct	1 ms	6608 KB	Output is correct
5	Correct	1 ms	6488 KB	Output is correct
6	Correct	1 ms	6492 KB	Output is correct
7	Correct	1 ms	6492 KB	Output is correct
8	Correct	1 ms	6492 KB	Output is correct
9	Correct	1 ms	6492 KB	Output is correct
10	Correct	1 ms	6492 KB	Output is correct
11	Correct	1 ms	6604 KB	Output is correct
12	Correct	1 ms	6492 KB	Output is correct
13	Correct	1 ms	6604 KB	Output is correct
14	Correct	2 ms	6492 KB	Output is correct
15	Correct	1 ms	6488 KB	Output is correct
16	Correct	1 ms	6492 KB	Output is correct
17	Correct	2 ms	6488 KB	Output is correct
18	Correct	7 ms	6492 KB	Output is correct
19	Correct	7 ms	6492 KB	Output is correct
20	Correct	7 ms	6492 KB	Output is correct
21	Correct	8 ms	6492 KB	Output is correct
22	Correct	8 ms	6492 KB	Output is correct
23	Correct	7 ms	6492 KB	Output is correct
24	Correct	7 ms	6492 KB	Output is correct
25	Correct	8 ms	6492 KB	Output is correct
26	Correct	7 ms	6492 KB	Output is correct
27	Correct	8 ms	6748 KB	Output is correct
28	Correct	7 ms	6492 KB	Output is correct

Subtask #3

21.0 / 21.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6488 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	1 ms	6492 KB	Output is correct
4	Correct	1 ms	6608 KB	Output is correct
5	Correct	1 ms	6488 KB	Output is correct
6	Correct	1 ms	6492 KB	Output is correct
7	Correct	1 ms	6492 KB	Output is correct
8	Correct	1 ms	6492 KB	Output is correct
9	Correct	1 ms	6492 KB	Output is correct
10	Correct	1 ms	6492 KB	Output is correct
11	Correct	1 ms	6604 KB	Output is correct
12	Correct	1 ms	6492 KB	Output is correct
13	Correct	1 ms	6604 KB	Output is correct
14	Correct	2 ms	6492 KB	Output is correct
15	Correct	1 ms	6488 KB	Output is correct
16	Correct	1 ms	6492 KB	Output is correct
17	Correct	2 ms	6488 KB	Output is correct
18	Correct	7 ms	6492 KB	Output is correct
19	Correct	7 ms	6492 KB	Output is correct
20	Correct	7 ms	6492 KB	Output is correct
21	Correct	8 ms	6492 KB	Output is correct
22	Correct	8 ms	6492 KB	Output is correct
23	Correct	7 ms	6492 KB	Output is correct
24	Correct	7 ms	6492 KB	Output is correct
25	Correct	8 ms	6492 KB	Output is correct
26	Correct	7 ms	6492 KB	Output is correct
27	Correct	8 ms	6748 KB	Output is correct
28	Correct	7 ms	6492 KB	Output is correct
29	Correct	818 ms	6664 KB	Output is correct
30	Correct	799 ms	6660 KB	Output is correct
31	Correct	795 ms	6492 KB	Output is correct
32	Correct	836 ms	6664 KB	Output is correct
33	Correct	832 ms	6660 KB	Output is correct
34	Correct	820 ms	6664 KB	Output is correct
35	Correct	813 ms	6660 KB	Output is correct
36	Correct	823 ms	6692 KB	Output is correct
37	Correct	841 ms	6656 KB	Output is correct
38	Correct	818 ms	6652 KB	Output is correct
39	Correct	826 ms	6740 KB	Output is correct
40	Correct	818 ms	6656 KB	Output is correct
41	Correct	814 ms	6740 KB	Output is correct
42	Correct	452 ms	6648 KB	Output is correct

Subtask #4

0 / 26.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6488 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	1 ms	6492 KB	Output is correct
4	Correct	1 ms	6608 KB	Output is correct
5	Correct	1 ms	6488 KB	Output is correct
6	Correct	1 ms	6492 KB	Output is correct
7	Correct	1 ms	6492 KB	Output is correct
8	Correct	1 ms	6492 KB	Output is correct
9	Correct	1 ms	6492 KB	Output is correct
10	Correct	1 ms	6492 KB	Output is correct
11	Correct	1 ms	6604 KB	Output is correct
12	Correct	1 ms	6492 KB	Output is correct
13	Correct	1 ms	6604 KB	Output is correct
14	Correct	2 ms	6492 KB	Output is correct
15	Correct	1 ms	6488 KB	Output is correct
16	Correct	1 ms	6492 KB	Output is correct
17	Correct	2 ms	6488 KB	Output is correct
18	Correct	7 ms	6492 KB	Output is correct
19	Correct	7 ms	6492 KB	Output is correct
20	Correct	7 ms	6492 KB	Output is correct
21	Correct	8 ms	6492 KB	Output is correct
22	Correct	8 ms	6492 KB	Output is correct
23	Correct	7 ms	6492 KB	Output is correct
24	Correct	7 ms	6492 KB	Output is correct
25	Correct	8 ms	6492 KB	Output is correct
26	Correct	7 ms	6492 KB	Output is correct
27	Correct	8 ms	6748 KB	Output is correct
28	Correct	7 ms	6492 KB	Output is correct
29	Correct	818 ms	6664 KB	Output is correct
30	Correct	799 ms	6660 KB	Output is correct
31	Correct	795 ms	6492 KB	Output is correct
32	Correct	836 ms	6664 KB	Output is correct
33	Correct	832 ms	6660 KB	Output is correct
34	Correct	820 ms	6664 KB	Output is correct
35	Correct	813 ms	6660 KB	Output is correct
36	Correct	823 ms	6692 KB	Output is correct
37	Correct	841 ms	6656 KB	Output is correct
38	Correct	818 ms	6652 KB	Output is correct
39	Correct	826 ms	6740 KB	Output is correct
40	Correct	818 ms	6656 KB	Output is correct
41	Correct	814 ms	6740 KB	Output is correct
42	Correct	452 ms	6648 KB	Output is correct
43	Execution timed out	7044 ms	9236 KB	Time limit exceeded
44	Halted	0 ms	0 KB	-

Subtask #5

0 / 13.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	6488 KB	Output is correct
2	Correct	1 ms	6492 KB	Output is correct
3	Correct	1 ms	6492 KB	Output is correct
4	Correct	1 ms	6608 KB	Output is correct
5	Correct	1 ms	6488 KB	Output is correct
6	Correct	1 ms	6492 KB	Output is correct
7	Correct	1 ms	6492 KB	Output is correct
8	Correct	1 ms	6492 KB	Output is correct
9	Correct	1 ms	6492 KB	Output is correct
10	Correct	1 ms	6492 KB	Output is correct
11	Correct	1 ms	6604 KB	Output is correct
12	Correct	1 ms	6492 KB	Output is correct
13	Correct	1 ms	6604 KB	Output is correct
14	Correct	2 ms	6492 KB	Output is correct
15	Correct	1 ms	6488 KB	Output is correct
16	Correct	1 ms	6492 KB	Output is correct
17	Correct	2 ms	6488 KB	Output is correct
18	Correct	7 ms	6492 KB	Output is correct
19	Correct	7 ms	6492 KB	Output is correct
20	Correct	7 ms	6492 KB	Output is correct
21	Correct	8 ms	6492 KB	Output is correct
22	Correct	8 ms	6492 KB	Output is correct
23	Correct	7 ms	6492 KB	Output is correct
24	Correct	7 ms	6492 KB	Output is correct
25	Correct	8 ms	6492 KB	Output is correct
26	Correct	7 ms	6492 KB	Output is correct
27	Correct	8 ms	6748 KB	Output is correct
28	Correct	7 ms	6492 KB	Output is correct
29	Correct	818 ms	6664 KB	Output is correct
30	Correct	799 ms	6660 KB	Output is correct
31	Correct	795 ms	6492 KB	Output is correct
32	Correct	836 ms	6664 KB	Output is correct
33	Correct	832 ms	6660 KB	Output is correct
34	Correct	820 ms	6664 KB	Output is correct
35	Correct	813 ms	6660 KB	Output is correct
36	Correct	823 ms	6692 KB	Output is correct
37	Correct	841 ms	6656 KB	Output is correct
38	Correct	818 ms	6652 KB	Output is correct
39	Correct	826 ms	6740 KB	Output is correct
40	Correct	818 ms	6656 KB	Output is correct
41	Correct	814 ms	6740 KB	Output is correct
42	Correct	452 ms	6648 KB	Output is correct
43	Execution timed out	7044 ms	9236 KB	Time limit exceeded
44	Halted	0 ms	0 KB	-