Submission #1011164

#	Time	Username	Problem	Language	Result	Execution time	Memory
1011164		GrindMachine	Hiring (IOI09_hiring)	C++17	100 / 100	366 ms	52164 KiB

hiring

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

template<typename T>
struct fenwick {
    int n;
    vector<T> tr;
    int LOG = 0;

    fenwick() {

    }

    fenwick(int n_) {
        n = n_;
        tr = vector<T>(n + 1);
        while((1<<LOG) <= n) LOG++;
    }

    int lsb(int x) {
        return x & -x;
    }

    void pupd(int i, T v) {
        for(; i <= n; i += lsb(i)){
            tr[i] += v;
        }
    }

    T sum(int i) {
        T res = 0;
        for(; i; i ^= lsb(i)){
            res += tr[i];
        }
        return res;
    }

    T query(int l, int r) {
        if (l > r) return 0;
        T res = sum(r) - sum(l - 1);
        return res;
    }

    int lower_bound(T s){
        // first pos with sum >= s
        if(sum(n) < s) return n+1;
        int i = 0;
        rev(bit,LOG-1,0){
            int j = i+(1<<bit);
            if(j > n) conts;
            if(tr[j] < s){
                s -= tr[j];
                i = j;
            }
        }

        return i+1;
    }

    int upper_bound(T s){
        return lower_bound(s+1);
    }
};

void solve(int test_case)
{
    ll n,m; cin >> n >> m;
    vector<pll> a(n);
    rep(i,n) cin >> a[i].ff >> a[i].ss;
    vector<ll> inds(n);
    iota(all(inds),0);

    auto cmp1 = [&](pll p1, pll p2){
        auto [s1,q1] = p1;
        auto [s2,q2] = p2;
        // s1/q1 < s2/q2?
        // s1*q2 < s2*q1?
        return s1*q2 < s2*q1;
    };

    auto cmp2 = [&](ll i, ll j){
        return cmp1(a[i],a[j]);
    };

    sort(all(inds),cmp2);
    sort(all(a),cmp1);

    vector<ll> b;
    rep(i,n) b.pb(a[i].ss);
    b.pb(-1);
    sort(all(b));
    b.resize(unique(all(b))-b.begin());
    ll siz = sz(b);
    fenwick<ll> fenw_cnt(siz+5), fenw_sum(siz+5);

    array<ll,4> best = {-1,-1,1,-1};

    rep(i,n){
        ll ind = lower_bound(all(b),a[i].ss)-b.begin();
        fenw_cnt.pupd(ind,1);
        fenw_sum.pupd(ind,a[i].ss);

        ll mx_sum = m*a[i].ss/a[i].ff;
        ll mx_ind = fenw_sum.upper_bound(mx_sum)-1;
        ll sum = fenw_sum.query(1,mx_ind);
        ll cnt = fenw_cnt.query(1,mx_ind);
        if(mx_ind+1 < siz){
            ll extra = (mx_sum-sum)/b[mx_ind+1];
            sum += extra*b[mx_ind+1];
            cnt += extra;
        }

        array<ll,4> ar = {cnt,sum*a[i].ff,a[i].ss,i};
        if(cnt > best[0]){
            best = ar;
        }
        else if(cnt == best[0]){
            if(cmp1({ar[1],ar[2]},{best[1],best[2]})){
                best = ar;
            }            
        }
    }

    ll pos = best[3];
    set<pll> st;
    rep(i,pos+1){
        st.insert({a[i].ss,i});
    }

    ll mx_sum = m*a[pos].ss/a[pos].ff;
    ll sum = 0;
    vector<ll> ans;

    for(auto [x,i] : st){
        sum += x;
        if(sum > mx_sum) break;
        ans.pb(inds[i]+1);
    }

    assert(sz(ans) == best[0]);
    sort(all(ans));
    cout << sz(ans) << endl;
    trav(x,ans) cout << x << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 30 / 30
• Subtask 2: 28 / 28
• Subtask 3: 6 / 6
• Subtask 4: 6 / 6
• Subtask 5: 6 / 6
• Subtask 6: 6 / 6
• Subtask 7: 6 / 6
• Subtask 8: 6 / 6
• Subtask 9: 6 / 6