제출 #1279828

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1279828		MinhKien	Nivelle (COCI20_nivelle)	C++17	110 / 110	174 ms	8876 KiB

nivelle

#include <iostream>
#include <string>

using namespace std;

const int N = 1e5 + 10;

int n, Log2[N], a[N][20];
string s;

int get(int l, int r) {
    int kk = Log2[r - l + 1];
    return a[l][kk] | a[r - (1 << kk) + 1][kk];
}

int Find(int i, int l, int val) {
    int r = n, ans = -1;
    while (l <= r) {
        int mid = (l + r) >> 1;

        int kk = __builtin_popcount(get(i, mid));
        if (kk > val) r = mid - 1;
        else {
            ans = mid;
            l = mid + 1;
        }
    }
    return ans;
}

int main() {
    cin.tie(0); cout.tie(0);
    ios_base::sync_with_stdio(false);

    cin >> n >> s;
    s = " " + s;

    for (int i = 1; i <= n; ++i) {
        if (i >= 2) Log2[i] = Log2[i >> 1] + 1;
        a[i][0] = 1 << (s[i] - 'a');
    }

    for (int j = 1; (1 << j) <= n; ++j) {
        for (int i = 1; i + (1 << j) - 1 <= n; ++i) {
            a[i][j] = a[i][j - 1] | a[i + (1 << (j - 1))][j - 1];
        }
    }

    double Min = 1e9;
    int L, R;
    for (int i = 1; i <= n; ++i) {
        int la = i;
        for (int j = 1; j <= 26; ++j) {
            la = Find(i, la, j);
            if (la == -1) break;

            double cur = (double)j / (double)(la - i + 1);
            if (cur < Min) {
                Min = cur;
                L = i;
                R = la;
            }
        }
    }

    cout << L << " " << R << "\n";

    return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 17 / 17
• Subtask 3: 13 / 13
• Subtask 4: 25 / 25
• Subtask 5: 48 / 48