제출 #1279827

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1279827		MinhKien	Nivelle (COCI20_nivelle)	C++17	62 / 110	1096 ms	1684 KiB

nivelle

#include <iostream>
#include <string>

using namespace std;

const int N = 1e5 + 10;

int n;
string s;

struct SEG {
    int val[N << 2];

    void build(int l, int r, int id) {
        if (l == r) {
            val[id] = 1 << (s[l] - 'a');
            return;
        }

        int mid = (l + r) >> 1;
        build(l, mid, id << 1);
        build(mid + 1, r, id << 1 | 1);

        val[id] = val[id << 1] | val[id << 1 | 1];
    }

    int get(int l, int r, int u, int v, int id) {
        if (l > v || r < u) return 0;

        if (l >= u && r <= v) return val[id];

        int mid = (l + r) >> 1;
        return get(l, mid, u, v, id << 1) | get(mid + 1, r, u, v, id << 1 | 1);
    }
} seg;

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(seg.get(1, n, i, mid, 1));
        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;
    seg.build(1, n, 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: 0 / 48