Submission #197099

#	Time	Username	Problem	Language	Result	Execution time	Memory
197099		stefdasca	Dancing Elephants (IOI11_elephants)	C++14	100 / 100	6350 ms	17088 KiB

elephants

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

const int mxN=150000, B=550, mxBC=300;
int n, l, *x, uc, bc, r[mxBC];
map<int, int> mp;
vector<int> v[mxBC];
vector<array<int, 2>> w[mxBC];

void init(int N, int L, int X[])
{
    n=N, l=L, x=X;
    for(int i=0; i<n; ++i)
        ++mp[x[i]];
}

void bb(int i)
{
    w[i]=vector<array<int, 2>>(v[i].size());
    for(int j1=(int)v[i].size()-1, j2=v[i].size(); ~j1; --j1)
    {
        while(v[i][j2-1]>v[i][j1]+l)
            --j2;
        w[i][j1]=j2<v[i].size()?array<int, 2> {w[i][j2][0]+1, w[i][j2][1]}:
                 array<int, 2> {1, v[i][j1]+l};
    }
}
void bld()
{
    bc=0;
    for(pair<int, int> p : mp)
    {
        if(!bc||v[bc-1].size()>=B)
            v[bc++].clear();
        v[bc-1].push_back(p.first);
    }
    for(int i=0; i<bc; ++i)
    {
        r[i]=i+1<bc?v[i+1][0]-1:1e9;
        bb(i);
    }
}

void upd(int x, bool a)
{
    int c=-1;
    while(x>r[++c]);
    int p=lower_bound(v[c].begin(), v[c].end(), x)-v[c].begin();
    if(a)
        v[c].insert(v[c].begin()+p, x);
    else
        v[c].erase(v[c].begin()+p);
    bb(c);
}

int update(int i, int y)
{
    if(uc++%B==0)
        bld();
    --mp[x[i]];
    if(!mp[x[i]])
    {
        upd(x[i], 0);
        mp.erase(x[i]);
    }
    if(!mp[y])
        upd(y, 1);
    ++mp[y];
    x[i]=y;
    int a=0;
    for(int i=0, c=-1; i<bc; ++i)
    {
        int p=upper_bound(v[i].begin(), v[i].end(), c)-v[i].begin();
        if(p<v[i].size())
        {
            a+=w[i][p][0];
            c=w[i][p][1];
        }
    }
    return a;
}

Compilation message (stderr)

elephants.cpp: In function 'void bb(int)':
elephants.cpp:25:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         w[i][j1]=j2<v[i].size()?array<int, 2> {w[i][j2][0]+1, w[i][j2][1]}:
                  ~~^~~~~~~~~~~~
elephants.cpp: In function 'int update(int, int)':
elephants.cpp:75:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if(p<v[i].size())
            ~^~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 24 / 24
• Subtask 4: 47 / 47
• Subtask 5: 3 / 3