Submission #202171

#	Time	Username	Problem	Language	Result	Execution time	Memory
202171		Segtree	Bulldozer (JOI17_bulldozer)	C++14	75 / 100	986 ms	66584 KiB

bulldozer

#include<iostream>
#include<algorithm>
#include<vector>
#include<queue>
#include<set>
#include<complex>
#include<math.h>
#include<unordered_set>
#include<unordered_map>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> P;
typedef complex<long double> C;
#define chmax(a,b) a=max(a,b)
#define chmin(a,b) a=min(a,b)
#define all(x) x.begin(),x.end()
#define rep(i,n) for(int i=0;i<n;i++)
#define mod 1000000007
#define mad(a,b) a=(a+b)%mod
#define PI acosl(-1)
#define N 2048
ll n,x[N],y[N],w[N];

ll dat1[2*N],dat2[2*N],dat3[2*N];
void init(){
    rep(i,2*N){
	dat1[i]=1e17;
	dat2[i]=-1e17;
	dat3[i]=0;
    }
}
void upd(ll i,ll x){
    //cout<<"update"<<i<<" "<<x<<" ";
    i+=N;
    dat1[i]=dat2[i]=x;
    for(;i>1;i>>=1){
	dat1[i/2]=min(dat1[i],dat1[i^1]);
	dat2[i/2]=max(dat2[i],dat2[i^1]);
	int a=i,b=i^1; if(a>b)swap(a,b);
	dat3[i/2]=max(dat2[b]-dat1[a],max(dat3[a],dat3[b]));
    }
    //cout<<dat3[1]<<endl;
}
ll rsm(){
    return dat3[1];
}
/*ll rsm(){
    ll mi=0,res=0;
    rep(i,n){
	chmin(mi,dat1[N+i+1]);
	chmax(res,dat1[N+i+1]-mi);
    }
    assert(res>=dat3[1]);
    return res;
}*/

ll pl[N];
ll swp(int a,int b){//cout<<"swp"<<w[a]<<" "<<w[b]<<endl;
    if(pl[a]>pl[b])swap(a,b);
    upd(pl[a]+1,dat1[N+pl[a]]+w[b]);
    swap(pl[a],pl[b]);//cout<<"rsm"<<rsm()<<endl;
    return rsm();
}

struct qry{
    ld arg;
    ll a,b;
    bool operator<(const qry&key)const{
	return this->arg<key.arg;
    }
};

int main(){
    cin>>n;
    rep(i,n){
	cin>>x[i]>>y[i]>>w[i];
    }
    rep(i,n)rep(j,n-1){
	bool sw=0;
	if(y[j]!=y[j+1])sw=y[j]>y[j+1];
	else if(x[j]!=x[j+1])sw=x[j]<x[j+1];
	if(sw){
	    swap(x[j],x[j+1]);
	    swap(y[j],y[j+1]);
	    swap(w[j],w[j+1]);
	}
    }
    init();
    ll rui=0;
    upd(0,rui);
    rep(i,n){
	rui+=w[i];
	upd(i+1,rui);
	pl[i]=i;
    }
    
    vector<qry> Q;
    rep(i,n)rep(j,i){
	ld vl=atan2(y[i]-y[j],x[i]-x[j]);
	ld vr=atan2(y[j]-y[i],x[j]-x[i]);
	//cout<<"atan"<<w[i]<<" "<<w[j]<<" "<<vl<<" "<<vr<<endl;
	Q.push_back((struct qry){max(vl,vr),i,j});
    }
    sort(all(Q));
    ll ans=0;
    chmax(ans,rsm());
    rep(i,Q.size()){
	chmax(ans,swp(Q[i].a,Q[i].b));
    }
    cout<<ans<<endl;
}

Compilation message (stderr)

bulldozer.cpp: In function 'int main()':
bulldozer.cpp:18:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define rep(i,n) for(int i=0;i<n;i++)
bulldozer.cpp:108:9:
     rep(i,Q.size()){
         ~~~~~~~~~~             
bulldozer.cpp:108:5: note: in expansion of macro 'rep'
     rep(i,Q.size()){
     ^~~

• Subtask 1: 0 / 5
• Subtask 2: 20 / 20
• Subtask 3: 35 / 35
• Subtask 4: 20 / 20
• Subtask 5: 0 / 20