Submission #875756

#	Time	Username	Problem	Language	Result	Execution time	Memory
875756		Requiem	Cake 3 (JOI19_cake3)	C++17	100 / 100	756 ms	238124 KiB

cake3

#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#define MOD 1000000007
#define INF 1e18
#define fi first
#define se second
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORD(i,a,b) for(int i=a;i>=b;i--)
#define sz(a) ((int)(a).size())
#define endl '\n'
#define pi 3.14159265359
#define TASKNAME "cake3"
#define all(a) a.begin(),a.end()
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }
using namespace std;
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
typedef vector<int> vi;
const int MAXN = 3e5 + 9;
int n,m,a[MAXN],ans=INF;
ii p[MAXN];
vector<int> listval;
vector<int> valpos[MAXN];
vector<int> pre[MAXN<<2];
vector<int> wavelet[MAXN<<2];
vector<int> bit[MAXN<<2];
int getval(int x){
    return lower_bound(all(listval),x) - listval.begin() + 1;
}
void merged(int node,int a,int b){
     int ptr1 = 0, ptr2 = 0, prebit = 0, presum = 0;
     bit[node].pb(0);
     pre[node].pb(0);
     while(ptr1 < wavelet[a].size() or ptr2 < wavelet[b].size()){
        if (ptr1 == wavelet[a].size()){
            wavelet[node].pb(wavelet[b][ptr2++]);
            bit[node].pb(prebit);
            presum = presum + p[wavelet[b][ptr2-1]].fi;
            pre[node].pb(presum);

        }
        else if (ptr2 == wavelet[b].size()){
            wavelet[node].pb(wavelet[a][ptr1++]);
            bit[node].pb(++prebit);
            presum = presum + p[wavelet[a][ptr1-1]].fi;
            pre[node].pb(presum);

        }
        else if (wavelet[a][ptr1] < wavelet[b][ptr2]){
            wavelet[node].pb(wavelet[a][ptr1++]);
            bit[node].pb(++prebit);
            presum = presum + p[wavelet[a][ptr1-1]].fi;
            pre[node].pb(presum);
        }
        else {
            wavelet[node].pb(wavelet[b][ptr2++]);
            bit[node].pb(prebit);
            presum = presum + p[wavelet[b][ptr2-1]].fi;
            pre[node].pb(presum);
        }
     }
}
void build(int node,int l,int r){
    if (l==r){
        int presum = 0;
        pre[node].pb(0);
        for(auto x: valpos[l]){
            presum += listval[l-1];
            wavelet[node].pb(x);
            pre[node].pb(presum);
        }
        return;
    }
    int mid = (l+r)>>1;
    build(node<<1,l,mid);
    build(node<<1|1,mid+1,r);
    int id1 = 0, id2 = 0;
    merged(node,node<<1,node<<1|1);
}
int getkth(int node,int l,int r,int u,int v,int k){
    if (l==r){
        return k * listval[l-1];
    }
    if (u>v) return 0;
    int mid = (l+r)>>1;
    int poslu = bit[node][u] + (bit[node][u] - bit[node][u-1] == 0);
    int poslv = bit[node][v];
    int posru = u - bit[node][u] + (bit[node][u] - bit[node][u-1] == 1);
    int posrv = v - bit[node][v];
//    cout<<l<<' '<<r<<' '<<poslu<<' '<<poslv<<' '<<posru<<' '<<posrv<<' '<<k<<endl;
    if (posrv - posru + 1 >= k) {
        return getkth(node<<1|1,mid+1,r,posru,posrv,k);
    }
    else{
//        cout<<"ADD:"<<pre[node<<1|1][posrv] - pre[node<<1|1][posru-1]<<endl;
        return pre[node<<1|1][posrv] - pre[node<<1|1][posru-1] + getkth(node<<1,l,mid,poslu,poslv,k-posrv+posru-1);
    }
}
int C(int l,int r){
    return getkth(1,1,sz(listval),l,r,m) - (p[r].se - p[l].se)*2;
}
int dp[MAXN];
void dnc(int l,int r,int optl,int optr){
    ii best = {-INF,-1};
    int mid = (l+r)>>1;
    if (l>r) return;
    for(int i=max(mid+m-1,optl);i<=optr;i++){
        best = max(best, ii(C(mid,i),i));
    }
    dp[mid] = best.fi;
    int opt = best.se;
    dnc(l,mid-1,optl,opt);
    dnc(mid+1,r,opt,optr);
}
main()
{
    fast;
    if (fopen(TASKNAME".inp","r")){
        freopen(TASKNAME".inp","r",stdin);
        freopen(TASKNAME".out","w",stdout);
    }
    cin>>n>>m;
    for(int i=1;i<=n;i++){
        cin>>p[i].fi>>p[i].se;
        listval.pb(p[i].fi);
    }
    sort(listval.begin(),listval.end());
    listval.erase(unique(all(listval)),listval.end());
    sort(p+1,p+1+n,[](const ii &a,const ii &b){
        return a.se < b.se;
    });
    ans=-INF;
    for(int i=1;i<=n;i++){
        int x = getval(p[i].fi);
        valpos[x].pb(i);
    }
    build(1,1,sz(listval));
    dnc(1,n-m+1,1,n);
    for(int i=1;i<=n-m+1;i++){
        maximize(ans, dp[i]);
    }
//    cout<<endl;
    cout<<ans<<endl;
}

Compilation message (stderr)

cake3.cpp: In function 'void merged(long long int, long long int, long long int)':
cake3.cpp:37:17: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |      while(ptr1 < wavelet[a].size() or ptr2 < wavelet[b].size()){
      |            ~~~~~^~~~~~~~~~~~~~~~~~~
cake3.cpp:37:45: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |      while(ptr1 < wavelet[a].size() or ptr2 < wavelet[b].size()){
      |                                        ~~~~~^~~~~~~~~~~~~~~~~~~
cake3.cpp:38:18: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |         if (ptr1 == wavelet[a].size()){
      |             ~~~~~^~~~~~~~~~~~~~~~~~~~
cake3.cpp:45:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |         else if (ptr2 == wavelet[b].size()){
      |                  ~~~~~^~~~~~~~~~~~~~~~~~~~
cake3.cpp: In function 'void build(long long int, long long int, long long int)':
cake3.cpp:80:9: warning: unused variable 'id1' [-Wunused-variable]
   80 |     int id1 = 0, id2 = 0;
      |         ^~~
cake3.cpp:80:18: warning: unused variable 'id2' [-Wunused-variable]
   80 |     int id1 = 0, id2 = 0;
      |                  ^~~
cake3.cpp: At global scope:
cake3.cpp:118:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  118 | main()
      | ^~~~
cake3.cpp: In function 'int main()':
cake3.cpp:122:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  122 |         freopen(TASKNAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
cake3.cpp:123:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  123 |         freopen(TASKNAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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