Submission #154415

#	Time	Username	Problem	Language	Result	Execution time	Memory
154415		arnold518	Cake 3 (JOI19_cake3)	C++14	100 / 100	1334 ms	202476 KiB

cake3

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 2e5;

struct Cake
{
    int V, C;
    bool operator < (const Cake &p) { return C<p.C; }
}A[MAXN+10];
int N, M, S;
ll ans=-1e18;

vector<int> comp;
int getcomp(int x) { return lower_bound(comp.begin(), comp.end(), x)-comp.begin(); }

struct Node
{
    ll cnt, sum;
    Node *lc, *rc;
    Node() : cnt(0), sum(0), lc(NULL), rc(NULL) {}
};
Node *tree[MAXN+10];

void makeTree(Node *node, int tl, int tr)
{
    if(tl==tr) return;
    int mid=tl+tr>>1;
    node->lc=new Node();
    node->rc=new Node();
    makeTree(node->lc, tl, mid);
    makeTree(node->rc, mid+1, tr);
}

Node *addTree(Node *node, int tl, int tr, int pos)
{
    if(pos<tl || tr<pos) return node;
    Node *ret=new Node();
    if(tl==tr)
    {
        ret->cnt=node->cnt+1;
        ret->sum=node->sum+comp[tl];
        return ret;
    }
    int mid=tl+tr>>1;
    ret->lc=addTree(node->lc, tl, mid, pos);
    ret->rc=addTree(node->rc, mid+1, tr, pos);
    ret->cnt=ret->lc->cnt+ret->rc->cnt;
    ret->sum=ret->lc->sum+ret->rc->sum;
    return ret;
}

ll query(Node *nodel, Node *noder, int tl, int tr, ll k)
{
    if(tl==tr) return comp[tl]*min(k, noder->cnt-nodel->cnt);
    int mid=tl+tr>>1;
    ll t=noder->rc->cnt-nodel->rc->cnt;
    if(k>t) return query(nodel->lc, noder->lc, tl, mid, k-t)+noder->rc->sum-nodel->rc->sum;
    else return query(nodel->rc, noder->rc, mid+1, tr, k);
}

void solve(int sl, int sr, int el, int er)
{
    if(sl>sr) return;
    int i, j;
    int smid=sl+sr>>1, emid=er; ll val=-1e18;
    for(i=max(smid+M-1, el); i<=er; i++)
    {
        ll now=query(tree[smid-1], tree[i], 0, S-1, M)-2ll*(A[i].C-A[smid].C);
        //printf("%d %d %lld\n", smid, i, now);
        if(now>val) val=now, emid=i;
    }
    ans=max(ans, val);
    solve(sl, smid-1, el, emid);
    solve(smid+1, sr, emid, er);
}

int main()
{
    int i, j;

    scanf("%d%d", &N, &M);
    for(i=1; i<=N; i++) scanf("%d%d", &A[i].V, &A[i].C), comp.push_back(A[i].V);
    sort(A+1, A+N+1);

    sort(comp.begin(), comp.end());
    comp.erase(unique(comp.begin(), comp.end()), comp.end());
    S=comp.size();

    tree[0]=new Node();
    makeTree(tree[0], 0, S-1);
    for(i=1; i<=N; i++) tree[i]=addTree(tree[i-1], 0, S-1, getcomp(A[i].V));

    solve(1, N, 1, N);
    printf("%lld", ans);
}

Compilation message (stderr)

cake3.cpp: In function 'void makeTree(Node*, int, int)':
cake3.cpp:32:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid=tl+tr>>1;
             ~~^~~
cake3.cpp: In function 'Node* addTree(Node*, int, int, int)':
cake3.cpp:49:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid=tl+tr>>1;
             ~~^~~
cake3.cpp: In function 'll query(Node*, Node*, int, int, ll)':
cake3.cpp:60:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid=tl+tr>>1;
             ~~^~~
cake3.cpp: In function 'void solve(int, int, int, int)':
cake3.cpp:70:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int smid=sl+sr>>1, emid=er; ll val=-1e18;
              ~~^~~
cake3.cpp:69:12: warning: unused variable 'j' [-Wunused-variable]
     int i, j;
            ^
cake3.cpp: In function 'int main()':
cake3.cpp:84:12: warning: unused variable 'j' [-Wunused-variable]
     int i, j;
            ^
cake3.cpp:86:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &N, &M);
     ~~~~~^~~~~~~~~~~~~~~~
cake3.cpp:87:56: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(i=1; i<=N; i++) scanf("%d%d", &A[i].V, &A[i].C), comp.push_back(A[i].V);
                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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