oj.uz

Submission #775819

# Submission time Handle Problem Language Result Execution time Memory
775819 2023-07-07T04:38:16 Z marvinthang Chorus (JOI23_chorus) C++17
100 / 100
 1771 ms 91708 KB 
/*************************************
*    author: marvinthang             *
*    created: 07.07.2023 10:11:54    *
*************************************/

#include <bits/stdc++.h>

using namespace std;

#define                  fi  first
#define                  se  second
#define                left  ___left
#define               right  ___right
#define                TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define             MASK(i)  (1LL << (i))
#define           BIT(x, i)  ((x) >> (i) & 1)
#define  __builtin_popcount  __builtin_popcountll
#define              ALL(v)  (v).begin(), (v).end()
#define           REP(i, n)  for (int i = 0, _n = (n); i < _n; ++i)
#define          REPD(i, n)  for (int i = (n); i--; )
#define        FOR(i, a, b)  for (int i = (a), _b = (b); i < _b; ++i) 
#define       FORD(i, b, a)  for (int i = (b), _a = (a); --i >= _a; ) 
#define       FORE(i, a, b)  for (int i = (a), _b = (b); i <= _b; ++i) 
#define      FORDE(i, b, a)  for (int i = (b), _a = (a); i >= _a; --i) 
#define        scan_op(...)  istream & operator >> (istream &in, __VA_ARGS__ &u)
#define       print_op(...)  ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
    #include "debug.h"
#else
    #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
    #define DB(...) 23
    #define db(...) 23
    #define debug(...) 23
#endif

template <class U, class V> scan_op(pair <U, V>)  { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>)  { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>)  { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")";  else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
template <class A, class B> bool minimize(A &a, B b)  { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b)  { if (a < b) { a = b; return true; } return false; }

const long long INF = 1e18;

struct Line {
    long long a, b;
    int cnt;
    Line(long long a = 0, long long b = INF, int cnt = 0): a(a), b(b), cnt(cnt) {}
    long long eval(long long x) { return a * x + b; }
};

struct ConvexHullTrick {
    vector <Line> lines;
    int ptr;
    ConvexHullTrick(): ptr(0) {}
    bool bad(Line a, Line b, Line c) {
        return (long double) (c.b - a.b) / (a.a - c.a) < (long double) (b.b - a.b) / (a.a - b.a);
    }
    void addLine(long long a, long long b, int c) {
        Line l(a, b, c);
        while (lines.size() >= 2 && bad(lines.end()[-2], lines.back(), l)) lines.pop_back();
        lines.push_back(l);
    }
    Line getMin(long long x) {
        if (ptr >= (int) lines.size()) ptr = (int) lines.size() - 1;
        while (ptr < (int) lines.size() - 1 && lines[ptr].eval(x) > lines[ptr + 1].eval(x)) ++ptr;
        return lines[ptr];
    }
};

// end of template

const int MAX = 1e6 + 6;

int N, K;
string S;
vector <int> pos[2];

void init(void) {
	cin >> N >> K >> S;
}

long long dp[MAX], pref[MAX], add[MAX];
int cnt[MAX], pf[MAX];

void calc(long long c) {
	ConvexHullTrick cht;
	FORE(i, 1, N) {
		int j = i - 1;
		cht.addLine(-j, dp[j] + 1LL * j * j - pref[j] + add[j], cnt[j]);
		Line l = cht.getMin(i);
		dp[i] = l.eval(i) + pref[i] + c;
		cnt[i] = l.cnt + 1;
		j = pf[j];
		if (j < i) {
			if (minimize(dp[i], dp[j] + c)) cnt[i] = cnt[j] + 1;
			else if (dp[i] == dp[j] + c) minimize(cnt[i], cnt[j] + 1);
		}
	}
}

void process(void) {
	REP(i, 2 * N) pos[S[i] - 'A'].push_back(i);
	int j = 0;
	REP(i, N) {
		while (j < N && pos[1][j] < pos[0][i]) ++j;
		pf[i] = j;
		pref[i + 1] = pref[i] + j;
	}
	j = 0;
	REP(i, N) {
		j = max(j, i);
		while (j < N && pf[j] <= i) ++j;
		add[i] = 1LL * (j - i) * i + pref[i] - pref[j];
	}

	long long l = 0, r = INF;
	while (l <= r) {
		long long m = l + r >> 1;
		calc(m);
		if (cnt[N] <= K) r = m - 1;
		else l = m + 1;
	}
	calc(l);
	cout << dp[N] - l * K << '\n';

}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("chorus");
	init();
	process();
	cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

Compilation message

chorus.cpp: In function 'void process()':
chorus.cpp:121:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  121 |   long long m = l + r >> 1;
      |                 ~~^~~
chorus.cpp: In function 'int main()':
chorus.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
chorus.cpp:133:2: note: in expansion of macro 'file'
  133 |  file("chorus");
      |  ^~~~
chorus.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
chorus.cpp:133:2: note: in expansion of macro 'file'
  133 |  file("chorus");
      |  ^~~~

Subtask #1
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 0 ms 340 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 0 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 340 KB Output is correct

Subtask #2
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 0 ms 340 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 0 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 1 ms 340 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 340 KB Output is correct
23 Correct 1 ms 340 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 1 ms 340 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 0 ms 340 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 0 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 1 ms 340 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 340 KB Output is correct
23 Correct 1 ms 340 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 1 ms 340 KB Output is correct
29 Correct 5 ms 952 KB Output is correct
30 Correct 6 ms 928 KB Output is correct
31 Correct 6 ms 936 KB Output is correct
32 Correct 4 ms 760 KB Output is correct
33 Correct 4 ms 760 KB Output is correct
34 Correct 5 ms 908 KB Output is correct
35 Correct 5 ms 908 KB Output is correct
36 Correct 6 ms 772 KB Output is correct
37 Correct 7 ms 788 KB Output is correct
38 Correct 6 ms 916 KB Output is correct
39 Correct 6 ms 880 KB Output is correct
40 Correct 6 ms 924 KB Output is correct
41 Correct 5 ms 912 KB Output is correct
42 Correct 5 ms 888 KB Output is correct

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 0 ms 340 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 0 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 1 ms 340 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 340 KB Output is correct
23 Correct 1 ms 340 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 1 ms 340 KB Output is correct
29 Correct 5 ms 952 KB Output is correct
30 Correct 6 ms 928 KB Output is correct
31 Correct 6 ms 936 KB Output is correct
32 Correct 4 ms 760 KB Output is correct
33 Correct 4 ms 760 KB Output is correct
34 Correct 5 ms 908 KB Output is correct
35 Correct 5 ms 908 KB Output is correct
36 Correct 6 ms 772 KB Output is correct
37 Correct 7 ms 788 KB Output is correct
38 Correct 6 ms 916 KB Output is correct
39 Correct 6 ms 880 KB Output is correct
40 Correct 6 ms 924 KB Output is correct
41 Correct 5 ms 912 KB Output is correct
42 Correct 5 ms 888 KB Output is correct
43 Correct 87 ms 5836 KB Output is correct
44 Correct 142 ms 10128 KB Output is correct
45 Correct 137 ms 10168 KB Output is correct
46 Correct 109 ms 7480 KB Output is correct
47 Correct 116 ms 7584 KB Output is correct
48 Correct 120 ms 10248 KB Output is correct
49 Correct 120 ms 10280 KB Output is correct
50 Correct 150 ms 7500 KB Output is correct
51 Correct 147 ms 7520 KB Output is correct
52 Correct 118 ms 10276 KB Output is correct
53 Correct 122 ms 10216 KB Output is correct
54 Correct 139 ms 7724 KB Output is correct

Subtask #5
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 0 ms 340 KB Output is correct
11 Correct 0 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 0 ms 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 340 KB Output is correct
19 Correct 1 ms 340 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 340 KB Output is correct
23 Correct 1 ms 340 KB Output is correct
24 Correct 1 ms 340 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 1 ms 340 KB Output is correct
28 Correct 1 ms 340 KB Output is correct
29 Correct 5 ms 952 KB Output is correct
30 Correct 6 ms 928 KB Output is correct
31 Correct 6 ms 936 KB Output is correct
32 Correct 4 ms 760 KB Output is correct
33 Correct 4 ms 760 KB Output is correct
34 Correct 5 ms 908 KB Output is correct
35 Correct 5 ms 908 KB Output is correct
36 Correct 6 ms 772 KB Output is correct
37 Correct 7 ms 788 KB Output is correct
38 Correct 6 ms 916 KB Output is correct
39 Correct 6 ms 880 KB Output is correct
40 Correct 6 ms 924 KB Output is correct
41 Correct 5 ms 912 KB Output is correct
42 Correct 5 ms 888 KB Output is correct
43 Correct 87 ms 5836 KB Output is correct
44 Correct 142 ms 10128 KB Output is correct
45 Correct 137 ms 10168 KB Output is correct
46 Correct 109 ms 7480 KB Output is correct
47 Correct 116 ms 7584 KB Output is correct
48 Correct 120 ms 10248 KB Output is correct
49 Correct 120 ms 10280 KB Output is correct
50 Correct 150 ms 7500 KB Output is correct
51 Correct 147 ms 7520 KB Output is correct
52 Correct 118 ms 10276 KB Output is correct
53 Correct 122 ms 10216 KB Output is correct
54 Correct 139 ms 7724 KB Output is correct
55 Correct 1058 ms 68028 KB Output is correct
56 Correct 1586 ms 91572 KB Output is correct
57 Correct 1661 ms 91404 KB Output is correct
58 Correct 1156 ms 67604 KB Output is correct
59 Correct 1378 ms 80896 KB Output is correct
60 Correct 1522 ms 91596 KB Output is correct
61 Correct 1445 ms 91488 KB Output is correct
62 Correct 1490 ms 67660 KB Output is correct
63 Correct 1583 ms 68104 KB Output is correct
64 Correct 1458 ms 91496 KB Output is correct
65 Correct 1440 ms 91708 KB Output is correct
66 Correct 1771 ms 82396 KB Output is correct
67 Correct 1426 ms 91680 KB Output is correct