Submission #1041219

#	Time	Username	Problem	Language	Result	Execution time	Memory
1041219		SoulKnight	Self Study (JOI22_ho_t2)	C++17	0 / 100	1033 ms	4944 KiB

Main

#include "bits/stdc++.h"
using namespace std;
#define ll long long
#define ln '\n'

const int N = 3e5 + 5;
const ll INF = 5e18 + 5;

ll n, m, a[N], b[N];
inline ll ceil(ll x, ll y) {return (x + y - 1) / y;}
ll cnt(ll go_lesson, ll i, ll tar){
    return (m - go_lesson) - max(0LL, ceil(tar - a[i] * go_lesson, b[i]));
}

void solve(){
    cin >> n >> m;
    for (int i = 0; i < n; i++) cin >> a[i];
    for (int i = 0; i < n; i++) cin >> b[i];

    // ll l = 7, r = 7, ans = 0;
    ll l = 0, r = INF, ans = 0;
    while (l <= r){
        ll tar = (l + r) / 2;
        ll free, need; free = need = 0;

        for (int i = 0; i < n; i++){
            if (b[i] >= a[i]) {
                free += m;
                need += ceil(tar, b[i]);
            } else {
                // maybe don't blindly go to lessons
                ll lf = 0, rt = m, glit = 0;
                while (glit++ < 40){
                    ll tl = (2 * lf + rt) / 3;
                    ll tr = (lf + 2 * rt) / 3;
                    if (cnt(tl, i, tar) > cnt(tr, i, tar)) rt = tr;
                    else lf = tl;
                }

                ll best = lf;
                for (ll j = max(0LL, lf - 100); j <= min(m, lf + 100); j++){
                    if (cnt(j, i, tar) > cnt(best, i, tar)) best = j;
                }

                free += m - best;
                need += max(0LL, ceil(tar - a[i] * best, b[i]));
            }
            // cout << need << ' ' << free << ln;
        }
        if (need <= free) {ans = tar; l = tar + 1;}
        else r = tar - 1;
    }
    cout << ans << ln;
}

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

    // int TT; cin >> TT;
    // while (TT--) {solve();}

    solve();

}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 25
• Subtask 3: 0 / 27
• Subtask 4: 0 / 29
• Subtask 5: 0 / 9