Submission #737751

#	Time	Username	Problem	Language	Result	Execution time	Memory
737751		Shinori	Split the sequence (APIO14_sequence)	C++17	0 / 100	786 ms	13548 KiB

sequence

#include <bits/stdc++.h>
#define MAXN 201010
#define INF 987654321
using namespace std;
struct dat{
    int w,cnt;
    bool operator<(const dat &r)const{
        if(w!=r.w)return w<r.w;
        return cnt<r.cnt;
    }
}tree[MAXN<<2];
int lazy[MAXN<<2];
dat dp[MAXN];
vector<int>v[MAXN];
int a[MAXN],pre[MAXN],n,k;
long long int ans;
void prop(int no,int ns,int ne){
    if(ns!=ne){
        lazy[no<<1]+=lazy[no];
        lazy[no<<1|1]+=lazy[no];
    }
    tree[no].w+=lazy[no];
    lazy[no]=0;
}

void update1(int no,int ns,int ne,int an,dat val){
    if(an>ne || an<ns)return;
    if(ns==ne){
        tree[no]=val;
        return;
    }
    int mid=ns+ne>>1;
    update1(no<<1,ns,mid,an,val);
    update1(no<<1|1,mid+1,ne,an,val);
    tree[no]=max(tree[no<<1],tree[no<<1|1]);
}

void update2(int no,int ns,int ne,int as,int ae,int val){
    prop(no,ns,ne);
    if(as>ne || ns>ae)return;
    if(as<=ns && ne<=ae){
        lazy[no]+=val;
        prop(no,ns,ne);
        return;
    }
    int mid=ns+ne>>1;
    update2(no<<1,ns,mid,as,ae,val);
    update2(no<<1|1,mid+1,ne,as,ae,val);
    tree[no]=max(tree[no<<1],tree[no<<1|1]);
}

dat aliens(int c){
    for(int i=1 ; i<=n*4; i++)tree[i]={-INF,0};
    memset(lazy,0,sizeof(lazy));
    for(int i=1 ; i<=n ; i++){
        update1(1,1,n,i,dp[i-1]);
        update2(1,1,n,pre[i]+1,i,1);
        dp[i]={tree[1].w-c,tree[1].cnt+1};
    }
    return dp[n];
}

void bsearch(int low,int high){
    if(high<low)return;
    int mid=low+high>>1;
    dat x=aliens(mid);

    ans=min(ans,(long long int)x.w+(long long int)k*(long long int)mid);

    if(x.cnt<=k)bsearch(low,mid-1);
    else bsearch(mid+1,high);
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL), cout.tie(NULL);
    cin >> n >> k;
    for(int i=1 ; i<=n ; i++){
        cin>>a[i];
        v[a[i]].push_back(i);
    }

    for(int i=1 ; i<=n ; i++){
        for(int j=0 ; j<v[i].size() ; j++){
            if(j!=0)pre[v[i][j]]=v[i][j-1];
            else pre[v[i][j]]=0;
        }
    }
    ans=n;
    bsearch(0,n);
    cout<<(int)ans<<"\n";
    return 0;
}

Compilation message (stderr)

sequence.cpp: In function 'void update1(int, int, int, int, dat)':
sequence.cpp:32:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   32 |     int mid=ns+ne>>1;
      |             ~~^~~
sequence.cpp: In function 'void update2(int, int, int, int, int, int)':
sequence.cpp:46:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   46 |     int mid=ns+ne>>1;
      |             ~~^~~
sequence.cpp: In function 'void bsearch(int, int)':
sequence.cpp:65:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   65 |     int mid=low+high>>1;
      |             ~~~^~~~~
sequence.cpp: In function 'int main()':
sequence.cpp:84:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   84 |         for(int j=0 ; j<v[i].size() ; j++){
      |                       ~^~~~~~~~~~~~

• Subtask 1: 0 / 11
• Subtask 2: 0 / 11
• Subtask 3: 0 / 11
• Subtask 4: 0 / 17
• Subtask 5: 0 / 21
• Subtask 6: 0 / 29