#include "shortcut.h"
using namespace std;
long long ans=1e18,lofn;
vector<long long>prf,dep,len;
long long precalc[3010][3010];
bool checklr(int lend,int rend){
vector<long long>dep2=dep,origd;
long long vl=0,mxpos=0;
for(int i=2;i<=lend;i++){
vl=max(vl,dep2[i]+len[i-1]+dep2[i-1]);
dep2[i]=max(dep2[i],dep2[i-1]+len[i-1]);
}
for(int i=dep.size();--i>rend;){
long long gameover=dep2[i]+len[i-1]+dep2[i-1];
if(vl<gameover)vl=gameover,mxpos=rend;
dep2[i-1]=max(dep2[i-1],dep2[i]+len[i-1]);
}
origd=dep2;
for(int i=lend+1;i<=rend;i++)
dep2[i]=max(dep2[i-1],prf[i]-prf[lend]+dep2[i]);
dep2[lend-1]=-1e18;
long long KY=prf[rend]-prf[lend]+lofn;
int pt=rend;
for(int i=rend;i>lend;i--){
while(pt>lend&&prf[i]-prf[pt-1]<=KY/2)
pt--;
long long tis=dep2[pt-1]+lofn+origd[rend]-prf[i]+prf[rend];
long long tis2=origd[i]+prf[i]+max(pt==lend?origd[lend]-prf[lend]:dep2[lend-1],precalc[pt][i-1]);
long long tis3=max(tis,tis2);
if(tis3>vl) mxpos=i,vl=tis3;
}
ans=min(ans,vl);
return mxpos==rend;
}
long long checkvl(int lend,int rend){
vector<long long>dep2=dep,len=len,origd;
long long vl=0;
for(int i=2;i<=lend;i++){
vl=max(vl,dep2[i]+len[i-1]+dep2[i-1]);
dep2[i]=max(dep2[i],dep2[i-1]+len[i-1]);
}
for(int i=dep.size();--i>rend;){
vl=max(vl,dep2[i]+len[i-1]+dep2[i-1]);
dep2[i-1]=max(dep2[i-1],dep2[i]+len[i-1]);
}
origd=dep2;
for(int i=lend+1;i<=rend;i++)
dep2[i]=max(dep2[i-1],prf[i]-prf[lend]+dep2[i]);
dep2[lend-1]=-1e18;
long long KY=prf[rend]-prf[lend]+lofn;
int pt=rend;
for(int i=rend;i>lend;i--){
while(pt>lend&&prf[i]-prf[pt-1]<=KY/2)
pt--;
long long tis=dep2[pt-1]+lofn+origd[rend]-prf[i]+prf[rend];
long long tis2=origd[i]+prf[i]+max(pt==lend?origd[lend]-prf[lend]:dep2[lend-1],precalc[pt][i-1]);
vl=max(vl,max(tis,tis2));
}
ans=min(ans,vl);
return vl;
}
void DNC(int l,int r,int opl,int opr){
if(l>r)return;
int mid=l+r>>1,opt=0;
long long VD=1e18;
for(int i=max(mid+1,opl);i<=opr;i++) {
long long k=checkvl(mid,i);
if(VD>k) VD=k,opt=i;
}
DNC(l,mid-1,opl,opt);
DNC(mid+1,r,opt,opr);
}
void binsearch(int l){
int L=l+1,R=dep.size()-1;
for(int i=L;i<=R;i++)
checklr(l,i);
}
long long find_shortcut(int n, vector<int> l, vector<int> d, int c) {
lofn=c;
dep=len={0};
prf={0,0};
for(auto i:l)
len.push_back(i),
prf.push_back(i);
for(auto i:d)
dep.push_back(i);
memset(precalc,-7,sizeof precalc);
for(int i=1;i<=n;i++)
prf[i]+=prf[i-1],precalc[i][i]=dep[i]-prf[i];
for(int i=n-1;i;i--) for(int j=i+1;j<=n;j++)
precalc[i][j]=max(precalc[i][j-1],dep[j]-prf[j]);
//DNC(1,n-1,1,n);
for(int i=1;i<n;i++)
binsearch(i);
return ans;
}
Compilation message
shortcut.cpp: In function 'void DNC(int, int, int, int)':
shortcut.cpp:64:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
64 | int mid=l+r>>1,opt=0;
| ~^~
shortcut.cpp: In function 'long long int find_shortcut(int, std::vector<int>, std::vector<int>, int)':
shortcut.cpp:87:5: error: 'memset' was not declared in this scope
87 | memset(precalc,-7,sizeof precalc);
| ^~~~~~
shortcut.cpp:2:1: note: 'memset' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
1 | #include "shortcut.h"
+++ |+#include <cstring>
2 | using namespace std;
