576 C

C. MP3

爆ll ==

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define P pair<int,int>
#define sc(x) scanf("%I64d",&x);
#define maxn 400005
vector<ll>v;
map<ll,ll>mp;
ll A[maxn];
ll len,K;
ll qp(ll n)
{
    ll a=2;
    ll ans=1;
    while(n)
    {
        if(n&1)
        {
            ans*=a;
        }
        if(a>=len||ans>=len){///防爆范围
            ans=len;
            return ans;
        }
        a*=a;
        n>>=1;

    }
    return ans;
}

ll sum[maxn];
void init()
{
    for(int i=1; i<=len; i++)
    {
        sum[i]+=sum[i-1]+mp[v[i-1]];
    }
}
bool check(ll x)
{
    ll n=len-K,t;
    for(int i=0; i<=n; i++)
    {
        t=0;
        t+=sum[i];
        t+=sum[len]-sum[len-n+i];
        if(t<=x)return true;
    }
    return false;
}
int main()
{
    ll n;
    ll I;
    sc(n);
    v.resize(n);
    sc(I);
    I*=8;
    for(ll i=0; i<n; i++)
    {
        sc(v[i]);
        mp[v[i]]++;
    }
    sort(v.begin(),v.end());
    len=unique(v.begin(),v.end())-v.begin();
    ll k=I/n;
    K=qp(k);
    init();
    if(len<=K)
    {
        puts("0");
        return 0;
    }
    ll l=1,r=n,mid;
    while(l+1<=r)
    {
        mid=(l+r)>>1;
        if(check(mid))
        {
            r=mid;
        }
        else l=mid+1;
    }
    if(check(l))
        cout<<l<<'
';
    else cout<<r<<'
';


}
/*
12 1
0 0 0 0 0 0 1 1 2 2 3 3
*/
原文地址:https://www.cnblogs.com/liulex/p/11273870.html