Submission #1090554

#	Time	Username	Problem	Language	Result	Execution time	Memory
1090554		gyg	Martian DNA (BOI18_dna)	C++17	40 / 100	2084 ms	13960 KiB

dna

#pragma GCC optimize("Ofast", "unroll-loops")
#pragma GCC target("avx2")
#include <bits/stdc++.h>
using namespace std;
#define arr array
#define pii pair<int, int>
const int MX_N = 2e5 + 5;

int n;
arr<int, MX_N> vl, rq;

arr<int, MX_N> scr;
set<pii> ord;
void upd(int i, int x) {
    ord.erase({scr[i], i});
    scr[i] += x;
    ord.insert({scr[i], i});
}
bool chck(int sz) {
    for (int i = 1; i <= n; i++) scr[i] = -rq[i];
    ord.clear();
    for (int i = 1; i <= sz; i++) scr[vl[i]]++;
    for (int i = 1; i <= n; i++) ord.insert({scr[i], i});
    if (ord.begin()->first >= 0) return true;
    
    for (int i = sz + 1; i <= n; i++) {
        upd(vl[i], 1), upd(vl[i - sz], -1);
        if (ord.begin()->first >= 0) return true;
    }
    return false;
}

int bn_srch() {
    int lw = 1, hgh = n;
    while (lw != hgh) {
        // cout << lw << " " << hgh << endl;
        int md = (lw + hgh) / 2;
        if (chck(md)) hgh = md;
        else lw = md + 1;
    }
    return ((chck(lw)) ? lw : -1);
}

int main() {
    // freopen("mrt.in", "r", stdin);
    cin.sync_with_stdio(false), cin.tie(0);
    int tmp1, tmp2; cin >> n >> tmp1 >> tmp2;
    for (int i = 1; i <= n; i++) { cin >> vl[i]; vl[i]++; }
    for (int i = 1; i <= tmp2; i++) { int x; cin >> x; cin >> rq[x + 1]; }

    if (!chck(n)) { cout << "impossible" << endl; exit(0); }

    int ans = bn_srch();
    cout << ans << endl;
}

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 0 / 28
• Subtask 4: 0 / 32