| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1104363 | Ludissey | Overtaking (IOI23_overtaking) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "overtaking.h"
#include <bits/stdc++.h>
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(), a.rend()
using namespace std;
int n,m;
long long X;
const int LOG=10;
vector<pair<long long,int>> b;
vector<vector<long long>> s; // time of bus i a la station j
vector<vector<vector<int>>> dep; // depasser par
vector<vector<pair<long long,int>>> sb; // sorted array of busses i at station
vector<vector<pair<long long,int>>> sb2; // sorted array of busses i at station
vector<vector<long long>> dp; // when it will arrive if it collides at n
vector<int> a;
int petit_lower(long long Y, int j){
int l=0,r=sz(sb2[j])-1;
int ans=-1;
while(l<=r){
int mid=(l+r)/2;
if(sb2[j][mid].first<Y){
ans=abs(sb2[j][mid].second);
l=mid+1;
}else{
r=mid-1;
}
}
return ans;
}
void init(long long L, signed N, std::vector<long long> T, std::vector<signed> W, long long _x, signed M, std::vector<signed> _s)
{
n=N; X=_x; m=M;
a.resize(m+1);
sb.resize(m+1);
sb2.resize(m+1);
a[m]=L;
for (int i = 0; i < m; i++) a[i]=_s[i];
for (int i = 0; i < n; i++) {
if(W[i]<=X) continue;
b.push_back({W[i],T[i]});
}
n=sz(b);
dep.resize(n,vector<vector<int>>(m,vector<int>(LOG,-1)));
s.resize(n, vector<int>(m+1));
sort(rall(b));
for (int i = 0; i < n; i++) { sb[0].push_back({b[i].second,i}); sb2[0].push_back({b[i].second,-i}); s[i][0]=b[i].second; }
for (int i = 1; i < m; i++)
{
sort(all(sb[i-1]));
sort(all(sb2[i-1]));
long long mx=0;
long long cmx=0;
int cmxI=-1;
for (int j = 0; j < n; j++)
{
int x=sb[i-1][j].second;
if(j>0&&sb[i-1][j].first!=sb[i-1][j-1].first){
mx=max(mx,cmx);
cmx=mx;
}
s[x][i]=max(mx,sb[i-1][j].first+b[x].first*(a[i]-a[i-1]));
if(s[x][i]>cmx) cmxI=x;
cmx=max(s[x][i],cmx);
dep[x][i-1][0]=cmxI;
sb[i].push_back({s[x][i],x});
sb2[i].push_back({s[x][i],-x});
}
}
sort(all(sb2[m-1]));
for (int k = 1; k < LOG; k++)
{
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
{
int p=1<<(k-1);
if(p+j>=m) continue;
if(dep[i][j][k-1]==-1) dep[i][j][k]=-1;
else {
dep[i][j][k]=dep[dep[i][j][k-1]][j+p][k-1];
}
}
}
}
dp.resize(n,vector<int>(m));
for (int i = 0; i < n; i++)
{
dp[i][m-1]=s[i][m-1];
}
for (int i = m-2; i >= 0; i--)
{
for (int j = 0; j < n; j++)
{
int l=1; int r=(m-1)-i;
int ans=-1;
int ansX=-1;
int _j=petit_lower(s[j][i],i);
while(l<=r&&_j>=0){
int mid=(l+r)/2;
int _mid=mid;
int x=_j;
int dst=i;
for (int k = LOG-1; k >= 0; k--)
{
if(mid&(1<<k)){
x=dep[x][dst][k];
dst+=(1<<k);
_mid-=(1<<k);
if(x<0) break;
}
}
if(x>=0&&s[x][dst]>=X*(a[dst]-a[i])+s[j][i]){
r=mid-1;
ans=dst;
ansX=x;
}else if(x==-1){
r=mid-1;
}
else{
l=mid+1;
}
}
if(ans==-1){
dp[j][i]=(long long)(X*(a[m-1]-a[i]))+s[j][i];
}else{
dp[j][i]=dp[ansX][ans];
}
}
}
return;
}
long long arrival_time(long long Y)
{
int l=1; int r=m-1;
int ans=-1;
int ansX=-1;
int pl=petit_lower(Y,0);
if(pl==-1||n==0) return X*a[m-1]+Y;
while(l<=r){
int mid=(l+r)/2;
int _mid=mid;
int x=pl;
int dst=0;
for (int k = log2(mid); k >= 0; k--)
{
if(mid&(1<<k)){
x=dep[x][dst][k];
dst+=(1<<k);
_mid-=(1<<k);
if(x<0) break;
}
}
if(x>=0&&s[x][dst]>=(long long)(X*(a[dst]))+Y){
r=mid-1;
ans=dst;
ansX=x;
}else if(x==-1){
r=mid-1;
}
else{
l=mid+1;
}
}
if(ans==-1){
return X*a[m-1]+Y;
}else{
return dp[ansX][ans];
}
}