Submission #844483

#	Time	Username	Problem	Language	Result	Execution time	Memory
844483		vjudge1	Nivelle (COCI20_nivelle)	C++17	37 / 110	1056 ms	13656 KiB

nivelle

#include<bits/stdc++.h>
using namespace std;

using ll = long long;
using ld = long double;
#define pb push_back
#define endl '\n'
#define fi first
#define se second
#define fio ios_base::sync_with_stdio(false);cin.tie(NULL);
#define CDIV(a,b) (((a)+(b)-(1))/(b))
const ll inf = 1e17 + 5;
const ll mod = 1e9 + 7;
const ll N = 1e3 + 30;

 
int mod_(int a, int b)
{
    if(a >= 0)return a % b;
    a += (-a/b + 1) * b;
    return a % b;
}


ld eps = 1e-9;

struct p{
    vector<int>pref;
    p()
    {
        pref.assign(26,0);
    }
    p operator-(const p& b)
    {
        p res;
        for(int i = 0; i < 26; ++i)
        {
            res.pref[i] = pref[i] - b.pref[i];
        }
        return res;
    }
};

void solve()
{
    int n;
    string a;
    cin >> n >> a;
    bool c = any_of(a.begin(), a.end(), [&](char ch){return ch != 'a' and ch != 'b';});
    if(!c)
    {
        a.pb('z');
        int cnt = 1, mx = 1, l = 0, maxl = 0, maxr = 0;
        for(int i = 1; i <= n; ++i)
        {
            if(a[i] != a[i - 1])
            {
                if(cnt > mx)
                {
                    mx = cnt;
                    maxl = l;
                    maxr = i - 1;
                }
                l = i;
                cnt = 1;
            }
            else cnt++;
        }
        if(2 * (maxr - maxl + 1) <= n)maxl = 0, maxr = n - 1;
        cout << maxl + 1 << ' ' << maxr + 1 << endl;
    }
    else
    {
        set<char>s;
        vector<p>pref(n);
        pref[0].pref[a[0] - 'a'] = 1;
        for(int i = 1; i < n; ++i)
        {
            pref[i] = pref[i - 1];
            pref[i].pref[a[i] - 'a']++;
        }
        long double ans = 1;
        int ansl = 0, ansr = 0;
        for(int l = 0; l < n; ++l)
        {
            for(int r = l + 1; r < n; ++r)
            {
                p col = pref[r] - (l ? pref[l - 1] : p());
                int cnt = 0;
                for(int i : col.pref)cnt += !!i;
                if((ld)cnt / (r - l + 1) < ans)
                {
                    ans = (ld)cnt / (r - l + 1);
                    ansl = l;
                    ansr = r;
                }
            }
        }
        cout << ansl + 1 << ' ' << ansr + 1 << endl;
    }
    
    
}

int main()
{
    fio;
    //int t; cin >> t; while(t--)
    {
        solve();
    }
}

• Subtask 1: 7 / 7
• Subtask 2: 17 / 17
• Subtask 3: 13 / 13
• Subtask 4: 0 / 25
• Subtask 5: 0 / 48