Submission #387372

#	Time	Username	Problem	Language	Result	Execution time	Memory
387372		wiwiho	Cake 3 (JOI19_cake3)	C++14	100 / 100	1006 ms	200168 KiB

cake3

#include <bits/stdc++.h>
#include <bits/extc++.h>

#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define ef(a) emplace_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define tomax(a, b) ((a) = max((a), (b)))
#define tomin(a, b) ((a) = min((a), (b)))
#define topos(a) ((a) = (((a) % MOD + MOD) % MOD))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
    if(pvaspace) b << " "; pvaspace=true;\
    b << pva;\
}\
b << "\n";}

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;

const ll MOD = 1000000007;
const ll MAX = 1LL << 60;

template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
    return o << '(' << p.F << ',' << p.S << ')';
}

ll ifloor(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a < 0) return (a - b + 1) / b;
    else return a / b;
}

ll iceil(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a > 0) return (a + b - 1) / b;
    else return a / b;
}

struct Node{
    int l = -1, r = -1;
    ll cnt = 0, sum = 0;
};

vector<Node> st(8e6);
int ts = 0;

int build(int l, int r){
    int id = ts++;
    if(l == r) return id;
    int m = (l + r) / 2;
    st[id].l = build(l, m);
    st[id].r = build(m + 1, r);
    return id;
}

int modify(int pos, ll v, int L, int R, int oid){
    int id = ts++;
    st[id] = st[oid];
//    cerr << "modify " << pos << " " << v << " " << L << " " << R << " " << oid << " " << id << "\n";
    if(L == R){
        st[id].cnt++;
        st[id].sum += v;
        return id;
    }
    int M = (L + R) / 2;
    if(pos <= M) st[id].l = modify(pos, v, L, M, st[id].l);
    else st[id].r = modify(pos, v, M + 1, R, st[id].r);
    st[id].sum = st[st[id].l].sum + st[st[id].r].sum;
    st[id].cnt = st[st[id].l].cnt + st[st[id].r].cnt;
    return id;
}

vector<int> discr(1, MAX);
ll findkth(int k, int l, int r, int id1, int id2){
//    cerr << "findkth " << k << " " << id1 << " " << id2 << " " << l << " " << r << "\n";
    if(st[id2].l == -1) return discr[l] * k;
    int m = (l + r) / 2;
    if(st[st[id2].l].cnt - st[st[id1].l].cnt >= k) return findkth(k, l, m, st[id1].l, st[id2].l);
    return st[st[id2].l].sum - st[st[id1].l].sum + findkth(k - st[st[id2].l].cnt + st[st[id1].l].cnt, m + 1, r, st[id1].r, st[id2].r);
}

void _print(int l, int r, int id){
    if(l == r){
        cerr  << st[id].cnt << "," << st[id].sum << " ";
        return;
    }
    int m = (l + r) / 2;
    _print(l, m, st[id].l);
    _print(m + 1, r, st[id].r);
}

int n, M, tn;
void print(int rt){
    _print(1, tn, rt);
    cerr << "\n";
}

vector<ll> dp;
vector<pll> a;
vector<ll> c;
vector<int> rt;

ll calc(int l, int r){
    if(r - l + 1 < M) return -MAX;
    ll tmp = findkth(M, 1, tn, rt[l - 1], rt[r]);
//    cerr << "calc " << l << " " << r << " " << tmp << " " << (c[r] - c[l]) << "\n";
    return tmp - 2 * (c[r] - c[l]);
}

void dfs(int l, int r, int tl, int tr){
    if(l > r) return;
    int m = (l + r) / 2;
    int pos = tl;
    dp[m] = calc(pos, m);
    for(int i = tl; i <= tr; i++){
        ll tmp = calc(i, m);
//        cerr << i << " " << m << " " << tmp << "\n";
        if(tmp > dp[m]){
            pos = i;
            dp[m] = tmp;
        }
    }
//    cerr << "test " << l << " " << r << " " << m << " " << tl << " " << tr << " " << pos << "\n";
    dfs(l, m - 1, tl, pos);
    dfs(m + 1, r, pos, tr);
}

int main(){
    StarBurstStream

    cin >> n >> M;
    a.resize(n + 1);
    dp.resize(n + 1, -MAX);
    c.resize(n + 1);
    rt.resize(n + 1);

    for(int i = 1; i <= n; i++){
        cin >> a[i].S >> a[i].F;
        discr.eb(a[i].S);
    }
    sort(discr.begin() + 1, discr.end(), greater<>());
    uni(discr);
    sort(a.begin() + 1, a.end());
    tn = discr.size() - 1;
//    printv(a, cerr);

    rt[0] = build(1, tn);
    for(int i = 1; i <= n; i++){
        c[i] = a[i].F;
        int id = lower_bound(iter(discr), a[i].S, greater<>()) - discr.begin();
//        cerr << id << " " << a[i] << "\n";
        rt[i] = modify(id, a[i].S, 1, tn, rt[i - 1]);
//        cerr << i << "  ";
//        print(rt[i]);
    }

    dfs(1, n, 1, n);
    cout << *max_element(iter(dp)) << "\n";

    return 0;
}

Compilation message (stderr)

cake3.cpp:97:22: warning: overflow in conversion from 'long long int' to 'std::vector<int>::value_type' {aka 'int'} changes value from '1152921504606846976' to '0' [-Woverflow]
   97 | vector<int> discr(1, MAX);
      |                      ^~~

• Subtask 1: 5 / 5
• Subtask 2: 19 / 19
• Subtask 3: 76 / 76