답안 #296382

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
296382 2020-09-10T14:02:13 Z Mlxa Monochrome Points (JOI20_monochrome) C++14
100 / 100
883 ms 11488 KB
#ifdef LC
#include "pch.h"
#else
#include <bits/stdc++.h>
#endif
using namespace std;
using ll = long long;
#define int ll
#define all(x) x.begin(), x.end()
#define x first
#define y second

const int INPUT_BUF = 1 << 12;
const int OUTPUT_BUF = 1 << 16;
char input[INPUT_BUF];
char output[OUTPUT_BUF];
int input_ptr = 0;
int input_len = 0;
int output_ptr = 0;

inline
bool check_eof() {
    if (input_ptr == input_len) {
        input_ptr = 0;
        input_len = fread(input, 1, INPUT_BUF, stdin);
    }
    return input_ptr == input_len;
}
inline
char get_char() {
    assert(!check_eof());
    return input[input_ptr++];
}
inline
char read_char() {
    char c = get_char();
    while (c <= ' ') {
        c = get_char();
    }
    return c;
}
inline
int read_int() {
    int sgn = +1;
    char c = read_char();
    if (c == '-') {
        sgn = -1;
        c = get_char();
    }
    int x = 0;
    while ('0' <= c && c <= '9') {
        x = 10 * x + c - '0';
        c = get_char();
    }
    return x * sgn;

}
inline
__attribute__((destructor))
void flush_output() {
    fwrite(output, 1, output_ptr, stdout);
    output_ptr = 0;
}
inline
void write(char c) {
    if (output_ptr == OUTPUT_BUF) {
        flush_output();
    }
    output[output_ptr++] = c;
}
inline
void write(signed x) {
    static const int LEN = 20;
    static char tmp[LEN];
    int n = 0;
    if (x < 0) {
        write('-');
        x *= -1;
    }
    while (!n || x) {
        tmp[n++] = (char)(x % 10 + '0');
        x /= 10;
    }
    while (n--) {
        write(tmp[n]);
    }
}
inline
void write(long long x) {
    static const int LEN = 20;
    static char tmp[LEN];
    int n = 0;
    if (x < 0) {
        write('-');
        x *= -1;
    }
    while (!n || x) {
        tmp[n++] = (char)(x % 10 + '0');
        x /= 10;
    }
    while (n--) {
        write(tmp[n]);
    }
}
inline
void write(string s) {
    for (char c : s) {
        write(c);
    }
}
inline
void write(const char *s) {
    for (const char *ptr = s; *ptr; ++ptr) {
        write(*ptr);
    }
}

const int N = 4e5 + 10;
int n;
char s[N];
vector<int> g[2];
int fen[N];
void clear() {
    fill_n(fen, N, 0);
}
void add(int i) {
    for (; i < N; i |= i + 1) {
        ++fen[i];
    }
}
int sum(int i) {
    int s = 0;
    for (; i >= 0; i = (i & (i + 1)) - 1) {
        s += fen[i];
    }
    return s;
}
int go[N];
int mem[N];
int counter = 0;
int func(int k) {
    ++counter;
    if (mem[k] != 0) {
        return mem[k];
    }
    int s = 0;
    for (int i = 0; i < (int)g[0].size(); ++i) {
        int j = (i + k) % (int)g[1].size();
        go[g[0][i]] = g[1][j];
        go[g[1][j]] = g[0][i];
    }
    clear();
    for (int i = n - 1; i >= 0; --i) {
        if (go[i] <= i) {
            s += sum(i) - sum(go[i]);
            add(go[i]);
        }
    }
    clear();
    for (int i = 0; i < n; ++i) {
        if (i <= go[i]) {
            s += sum(go[i]) - sum(i);
            add(go[i]);
        }
    }
    return mem[k] = -(s / 2);
}
int der(int k) {
    return func((k + 1) % n) - func(k);
}

int32_t main() {
#ifdef LC
    assert(freopen("input.txt", "r", stdin));
    //assert(freopen("output.txt", "w", stdout));
#endif
    ios::sync_with_stdio(0); cin.tie(0);
    
    n = read_int();
    n *= 2;
    for (int i = 0; i < n; ++i) {
        if ((s[i] = read_char()) == 'W') {
            g[0].push_back(i);
        } else {
            g[1].push_back(i);
        }
    }
    /*
    for (int i = 0; i < n / 2; ++i) {
        cerr << func(i) << " ";
    }
    cerr << endl;
    */
    int ans = min(func(0), func(n / 2 - 1));
    if (n <= 4) {
        ans = 0;
        for (int i = 0; i < n / 2; ++i) {
            ans = min(ans, func(i));
        }
    } else if (der(0) < 0) {
        int lef = 0, rig = n / 2 - 1;
        int bound = max(func(lef), func(rig));
        while (rig - lef > 1) {
            int mid = (lef + rig) / 2;
            if (der(mid) < 0 && func(mid) <= bound) {
                lef = mid;
            } else {
                rig = mid;
            }
        }
        ans = min(ans, func(rig));
    } else {
        int lef = 0, rig = n / 2 - 1;
        int bound = min(func(lef), func(rig));
        while (rig - lef > 1) {
            int mid = (lef + rig) / 2;
            if (der(mid) < 0 || func(mid) >= bound) {
                lef = mid; 
            } else {
                rig = mid;
            }
        }
        ans = min(ans, func(rig));
    }
    ans *= -1;
    write(ans);
    write('\n');
    cerr << counter << endl;
    return 0;
}
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 3456 KB Output is correct
2 Correct 4 ms 3456 KB Output is correct
3 Correct 4 ms 3456 KB Output is correct
4 Correct 4 ms 3456 KB Output is correct
5 Correct 5 ms 3456 KB Output is correct
6 Correct 4 ms 3456 KB Output is correct
7 Correct 4 ms 3456 KB Output is correct
8 Correct 5 ms 3456 KB Output is correct
9 Correct 5 ms 3456 KB Output is correct
10 Correct 5 ms 3456 KB Output is correct
11 Correct 5 ms 3456 KB Output is correct
12 Correct 5 ms 3456 KB Output is correct
13 Correct 6 ms 3456 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 3456 KB Output is correct
2 Correct 4 ms 3456 KB Output is correct
3 Correct 4 ms 3456 KB Output is correct
4 Correct 4 ms 3456 KB Output is correct
5 Correct 5 ms 3456 KB Output is correct
6 Correct 4 ms 3456 KB Output is correct
7 Correct 4 ms 3456 KB Output is correct
8 Correct 5 ms 3456 KB Output is correct
9 Correct 5 ms 3456 KB Output is correct
10 Correct 5 ms 3456 KB Output is correct
11 Correct 5 ms 3456 KB Output is correct
12 Correct 5 ms 3456 KB Output is correct
13 Correct 6 ms 3456 KB Output is correct
14 Correct 10 ms 3456 KB Output is correct
15 Correct 10 ms 3456 KB Output is correct
16 Correct 14 ms 3456 KB Output is correct
17 Correct 9 ms 3456 KB Output is correct
18 Correct 9 ms 3456 KB Output is correct
19 Correct 9 ms 3456 KB Output is correct
20 Correct 9 ms 3456 KB Output is correct
21 Correct 9 ms 3456 KB Output is correct
22 Correct 9 ms 3456 KB Output is correct
23 Correct 9 ms 3456 KB Output is correct
24 Correct 9 ms 3456 KB Output is correct
25 Correct 9 ms 3456 KB Output is correct
26 Correct 9 ms 3456 KB Output is correct
27 Correct 9 ms 3456 KB Output is correct
28 Correct 10 ms 3456 KB Output is correct
29 Correct 9 ms 3456 KB Output is correct
30 Correct 9 ms 3456 KB Output is correct
31 Correct 10 ms 3456 KB Output is correct
32 Correct 10 ms 3456 KB Output is correct
33 Correct 11 ms 3456 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 3456 KB Output is correct
2 Correct 4 ms 3456 KB Output is correct
3 Correct 4 ms 3456 KB Output is correct
4 Correct 4 ms 3456 KB Output is correct
5 Correct 5 ms 3456 KB Output is correct
6 Correct 4 ms 3456 KB Output is correct
7 Correct 4 ms 3456 KB Output is correct
8 Correct 5 ms 3456 KB Output is correct
9 Correct 5 ms 3456 KB Output is correct
10 Correct 5 ms 3456 KB Output is correct
11 Correct 5 ms 3456 KB Output is correct
12 Correct 5 ms 3456 KB Output is correct
13 Correct 6 ms 3456 KB Output is correct
14 Correct 10 ms 3456 KB Output is correct
15 Correct 10 ms 3456 KB Output is correct
16 Correct 14 ms 3456 KB Output is correct
17 Correct 9 ms 3456 KB Output is correct
18 Correct 9 ms 3456 KB Output is correct
19 Correct 9 ms 3456 KB Output is correct
20 Correct 9 ms 3456 KB Output is correct
21 Correct 9 ms 3456 KB Output is correct
22 Correct 9 ms 3456 KB Output is correct
23 Correct 9 ms 3456 KB Output is correct
24 Correct 9 ms 3456 KB Output is correct
25 Correct 9 ms 3456 KB Output is correct
26 Correct 9 ms 3456 KB Output is correct
27 Correct 9 ms 3456 KB Output is correct
28 Correct 10 ms 3456 KB Output is correct
29 Correct 9 ms 3456 KB Output is correct
30 Correct 9 ms 3456 KB Output is correct
31 Correct 10 ms 3456 KB Output is correct
32 Correct 10 ms 3456 KB Output is correct
33 Correct 11 ms 3456 KB Output is correct
34 Correct 17 ms 3584 KB Output is correct
35 Correct 16 ms 3584 KB Output is correct
36 Correct 17 ms 3584 KB Output is correct
37 Correct 16 ms 3584 KB Output is correct
38 Correct 16 ms 3584 KB Output is correct
39 Correct 17 ms 3584 KB Output is correct
40 Correct 16 ms 3584 KB Output is correct
41 Correct 15 ms 3584 KB Output is correct
42 Correct 16 ms 3584 KB Output is correct
43 Correct 17 ms 3712 KB Output is correct
44 Correct 17 ms 3584 KB Output is correct
45 Correct 15 ms 3584 KB Output is correct
46 Correct 18 ms 3712 KB Output is correct
47 Correct 17 ms 3636 KB Output is correct
48 Correct 16 ms 3584 KB Output is correct
49 Correct 17 ms 3584 KB Output is correct
50 Correct 24 ms 3584 KB Output is correct
51 Correct 16 ms 3584 KB Output is correct
52 Correct 18 ms 3584 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 3456 KB Output is correct
2 Correct 4 ms 3456 KB Output is correct
3 Correct 4 ms 3456 KB Output is correct
4 Correct 4 ms 3456 KB Output is correct
5 Correct 5 ms 3456 KB Output is correct
6 Correct 4 ms 3456 KB Output is correct
7 Correct 4 ms 3456 KB Output is correct
8 Correct 5 ms 3456 KB Output is correct
9 Correct 5 ms 3456 KB Output is correct
10 Correct 5 ms 3456 KB Output is correct
11 Correct 5 ms 3456 KB Output is correct
12 Correct 5 ms 3456 KB Output is correct
13 Correct 6 ms 3456 KB Output is correct
14 Correct 10 ms 3456 KB Output is correct
15 Correct 10 ms 3456 KB Output is correct
16 Correct 14 ms 3456 KB Output is correct
17 Correct 9 ms 3456 KB Output is correct
18 Correct 9 ms 3456 KB Output is correct
19 Correct 9 ms 3456 KB Output is correct
20 Correct 9 ms 3456 KB Output is correct
21 Correct 9 ms 3456 KB Output is correct
22 Correct 9 ms 3456 KB Output is correct
23 Correct 9 ms 3456 KB Output is correct
24 Correct 9 ms 3456 KB Output is correct
25 Correct 9 ms 3456 KB Output is correct
26 Correct 9 ms 3456 KB Output is correct
27 Correct 9 ms 3456 KB Output is correct
28 Correct 10 ms 3456 KB Output is correct
29 Correct 9 ms 3456 KB Output is correct
30 Correct 9 ms 3456 KB Output is correct
31 Correct 10 ms 3456 KB Output is correct
32 Correct 10 ms 3456 KB Output is correct
33 Correct 11 ms 3456 KB Output is correct
34 Correct 17 ms 3584 KB Output is correct
35 Correct 16 ms 3584 KB Output is correct
36 Correct 17 ms 3584 KB Output is correct
37 Correct 16 ms 3584 KB Output is correct
38 Correct 16 ms 3584 KB Output is correct
39 Correct 17 ms 3584 KB Output is correct
40 Correct 16 ms 3584 KB Output is correct
41 Correct 15 ms 3584 KB Output is correct
42 Correct 16 ms 3584 KB Output is correct
43 Correct 17 ms 3712 KB Output is correct
44 Correct 17 ms 3584 KB Output is correct
45 Correct 15 ms 3584 KB Output is correct
46 Correct 18 ms 3712 KB Output is correct
47 Correct 17 ms 3636 KB Output is correct
48 Correct 16 ms 3584 KB Output is correct
49 Correct 17 ms 3584 KB Output is correct
50 Correct 24 ms 3584 KB Output is correct
51 Correct 16 ms 3584 KB Output is correct
52 Correct 18 ms 3584 KB Output is correct
53 Correct 866 ms 10352 KB Output is correct
54 Correct 883 ms 11008 KB Output is correct
55 Correct 806 ms 10468 KB Output is correct
56 Correct 825 ms 10468 KB Output is correct
57 Correct 814 ms 10588 KB Output is correct
58 Correct 821 ms 11488 KB Output is correct
59 Correct 774 ms 10580 KB Output is correct
60 Correct 854 ms 10584 KB Output is correct
61 Correct 834 ms 10540 KB Output is correct
62 Correct 840 ms 10612 KB Output is correct
63 Correct 795 ms 10576 KB Output is correct
64 Correct 774 ms 10472 KB Output is correct
65 Correct 740 ms 10324 KB Output is correct
66 Correct 790 ms 10504 KB Output is correct
67 Correct 807 ms 10484 KB Output is correct
68 Correct 750 ms 10356 KB Output is correct
69 Correct 803 ms 10848 KB Output is correct
70 Correct 768 ms 10224 KB Output is correct
71 Correct 834 ms 10980 KB Output is correct
72 Correct 819 ms 10984 KB Output is correct
73 Correct 881 ms 10844 KB Output is correct