oj.uz

Submission #296380

# Submission time Handle Problem Language Result Execution time Memory
296380 2020-09-10T14:01:33 Z Mlxa Monochrome Points (JOI20_monochrome) C++14
35 / 100
 914 ms 6240 KB 
#ifdef LC
#include "pch.h"
#else
#include <bits/stdc++.h>
#endif
using namespace std;
#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;
}

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1920 KB Output is correct
2 Correct 3 ms 1920 KB Output is correct
3 Correct 3 ms 1920 KB Output is correct
4 Correct 4 ms 1920 KB Output is correct
5 Correct 4 ms 1920 KB Output is correct
6 Correct 4 ms 1920 KB Output is correct
7 Correct 4 ms 1920 KB Output is correct
8 Correct 4 ms 1920 KB Output is correct
9 Correct 4 ms 1920 KB Output is correct
10 Correct 4 ms 1920 KB Output is correct
11 Correct 6 ms 1920 KB Output is correct
12 Correct 5 ms 1920 KB Output is correct
13 Correct 5 ms 1920 KB Output is correct

Subtask #2
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1920 KB Output is correct
2 Correct 3 ms 1920 KB Output is correct
3 Correct 3 ms 1920 KB Output is correct
4 Correct 4 ms 1920 KB Output is correct
5 Correct 4 ms 1920 KB Output is correct
6 Correct 4 ms 1920 KB Output is correct
7 Correct 4 ms 1920 KB Output is correct
8 Correct 4 ms 1920 KB Output is correct
9 Correct 4 ms 1920 KB Output is correct
10 Correct 4 ms 1920 KB Output is correct
11 Correct 6 ms 1920 KB Output is correct
12 Correct 5 ms 1920 KB Output is correct
13 Correct 5 ms 1920 KB Output is correct
14 Correct 9 ms 1952 KB Output is correct
15 Correct 9 ms 1920 KB Output is correct
16 Correct 9 ms 1920 KB Output is correct
17 Correct 8 ms 1920 KB Output is correct
18 Correct 11 ms 1920 KB Output is correct
19 Correct 8 ms 1920 KB Output is correct
20 Correct 13 ms 1920 KB Output is correct
21 Correct 8 ms 1920 KB Output is correct
22 Correct 10 ms 1920 KB Output is correct
23 Correct 8 ms 1920 KB Output is correct
24 Correct 9 ms 1920 KB Output is correct
25 Correct 8 ms 1920 KB Output is correct
26 Correct 8 ms 1920 KB Output is correct
27 Correct 8 ms 1920 KB Output is correct
28 Correct 10 ms 2048 KB Output is correct
29 Correct 8 ms 1920 KB Output is correct
30 Correct 8 ms 1920 KB Output is correct
31 Correct 9 ms 1920 KB Output is correct
32 Correct 9 ms 1920 KB Output is correct
33 Correct 11 ms 2048 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1920 KB Output is correct
2 Correct 3 ms 1920 KB Output is correct
3 Correct 3 ms 1920 KB Output is correct
4 Correct 4 ms 1920 KB Output is correct
5 Correct 4 ms 1920 KB Output is correct
6 Correct 4 ms 1920 KB Output is correct
7 Correct 4 ms 1920 KB Output is correct
8 Correct 4 ms 1920 KB Output is correct
9 Correct 4 ms 1920 KB Output is correct
10 Correct 4 ms 1920 KB Output is correct
11 Correct 6 ms 1920 KB Output is correct
12 Correct 5 ms 1920 KB Output is correct
13 Correct 5 ms 1920 KB Output is correct
14 Correct 9 ms 1952 KB Output is correct
15 Correct 9 ms 1920 KB Output is correct
16 Correct 9 ms 1920 KB Output is correct
17 Correct 8 ms 1920 KB Output is correct
18 Correct 11 ms 1920 KB Output is correct
19 Correct 8 ms 1920 KB Output is correct
20 Correct 13 ms 1920 KB Output is correct
21 Correct 8 ms 1920 KB Output is correct
22 Correct 10 ms 1920 KB Output is correct
23 Correct 8 ms 1920 KB Output is correct
24 Correct 9 ms 1920 KB Output is correct
25 Correct 8 ms 1920 KB Output is correct
26 Correct 8 ms 1920 KB Output is correct
27 Correct 8 ms 1920 KB Output is correct
28 Correct 10 ms 2048 KB Output is correct
29 Correct 8 ms 1920 KB Output is correct
30 Correct 8 ms 1920 KB Output is correct
31 Correct 9 ms 1920 KB Output is correct
32 Correct 9 ms 1920 KB Output is correct
33 Correct 11 ms 2048 KB Output is correct
34 Correct 16 ms 1920 KB Output is correct
35 Correct 15 ms 1920 KB Output is correct
36 Correct 15 ms 1920 KB Output is correct
37 Correct 15 ms 2048 KB Output is correct
38 Correct 16 ms 1920 KB Output is correct
39 Correct 19 ms 1920 KB Output is correct
40 Correct 14 ms 1920 KB Output is correct
41 Correct 14 ms 1920 KB Output is correct
42 Correct 16 ms 1920 KB Output is correct
43 Correct 18 ms 1920 KB Output is correct
44 Correct 15 ms 1920 KB Output is correct
45 Correct 14 ms 1920 KB Output is correct
46 Correct 15 ms 1920 KB Output is correct
47 Correct 15 ms 1920 KB Output is correct
48 Correct 16 ms 2040 KB Output is correct
49 Correct 15 ms 2048 KB Output is correct
50 Correct 15 ms 1920 KB Output is correct
51 Correct 15 ms 1920 KB Output is correct
52 Correct 17 ms 1920 KB Output is correct

Subtask #4
0.0 / 65.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1920 KB Output is correct
2 Correct 3 ms 1920 KB Output is correct
3 Correct 3 ms 1920 KB Output is correct
4 Correct 4 ms 1920 KB Output is correct
5 Correct 4 ms 1920 KB Output is correct
6 Correct 4 ms 1920 KB Output is correct
7 Correct 4 ms 1920 KB Output is correct
8 Correct 4 ms 1920 KB Output is correct
9 Correct 4 ms 1920 KB Output is correct
10 Correct 4 ms 1920 KB Output is correct
11 Correct 6 ms 1920 KB Output is correct
12 Correct 5 ms 1920 KB Output is correct
13 Correct 5 ms 1920 KB Output is correct
14 Correct 9 ms 1952 KB Output is correct
15 Correct 9 ms 1920 KB Output is correct
16 Correct 9 ms 1920 KB Output is correct
17 Correct 8 ms 1920 KB Output is correct
18 Correct 11 ms 1920 KB Output is correct
19 Correct 8 ms 1920 KB Output is correct
20 Correct 13 ms 1920 KB Output is correct
21 Correct 8 ms 1920 KB Output is correct
22 Correct 10 ms 1920 KB Output is correct
23 Correct 8 ms 1920 KB Output is correct
24 Correct 9 ms 1920 KB Output is correct
25 Correct 8 ms 1920 KB Output is correct
26 Correct 8 ms 1920 KB Output is correct
27 Correct 8 ms 1920 KB Output is correct
28 Correct 10 ms 2048 KB Output is correct
29 Correct 8 ms 1920 KB Output is correct
30 Correct 8 ms 1920 KB Output is correct
31 Correct 9 ms 1920 KB Output is correct
32 Correct 9 ms 1920 KB Output is correct
33 Correct 11 ms 2048 KB Output is correct
34 Correct 16 ms 1920 KB Output is correct
35 Correct 15 ms 1920 KB Output is correct
36 Correct 15 ms 1920 KB Output is correct
37 Correct 15 ms 2048 KB Output is correct
38 Correct 16 ms 1920 KB Output is correct
39 Correct 19 ms 1920 KB Output is correct
40 Correct 14 ms 1920 KB Output is correct
41 Correct 14 ms 1920 KB Output is correct
42 Correct 16 ms 1920 KB Output is correct
43 Correct 18 ms 1920 KB Output is correct
44 Correct 15 ms 1920 KB Output is correct
45 Correct 14 ms 1920 KB Output is correct
46 Correct 15 ms 1920 KB Output is correct
47 Correct 15 ms 1920 KB Output is correct
48 Correct 16 ms 2040 KB Output is correct
49 Correct 15 ms 2048 KB Output is correct
50 Correct 15 ms 1920 KB Output is correct
51 Correct 15 ms 1920 KB Output is correct
52 Correct 17 ms 1920 KB Output is correct
53 Incorrect 914 ms 6240 KB Output isn't correct
54 Halted 0 ms 0 KB -