| # | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 953478 | 2024-03-26T03:07:08 Z | Pacybwoah | Sparklers (JOI17_sparklers) | C++17 | 1 ms | 344 KB |
#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
typedef long long ll;
int main(){
ios::sync_with_stdio(false);
cin.tie(0);
int n,k;
ll t;
cin>>n>>k>>t;
vector<ll> vec(n+1);
for(int i=1;i<=n;i++) cin>>vec[i];
ll l=0,r=2e9;
//l=8,r=9;
while(l<r){
ll mid=(l+r)>>1;
ll vt=2*mid*t;
int nowl=k-1,nowr=k+1;
ll cnt=1;
bool flag=0;
if(k>1){
if(vec[k]-vec[k-1]<=vt){
cnt++;
nowl=k-2;
ll pos=vec[k]-vt;
bool dir=0;
while(nowl>0||nowr<=n){
if(!dir){
while(nowl>0&&pos-vec[nowl]<=vt){
pos-=vt;
nowl--;
cnt++;
}
pos=vec[nowl+1];
if(nowr>n){
if(nowl<1) flag=1;
break;
}
else if(vec[nowr]-pos<=vt*cnt){
cnt++;
pos=vec[nowr];
nowr++;
dir=!dir;
}
else{
break;
}
}
else{
while(nowr<=n&&vec[nowr]-pos<=vt){
pos+=vt;
nowr++;
cnt++;
}
pos=vec[nowr-1];
if(nowl<1){
if(nowr>n) flag=1;
break;
}
else if(pos-vec[nowl]<=vt*cnt){
cnt++;
pos=vec[nowl];
nowl--;
dir=!dir;
}
else{
break;
}
}
}
if(nowl<1&&nowr>n) flag=1;
}
}
if(k<n){
if(vec[k+1]-vec[k]<=vt){
cnt=2;
nowl=k-1,nowr=k+2;
ll pos=vec[k]+vt;
bool dir=1;
while(nowl>0||nowr<=n){
//cout<<nowl<<" "<<nowr<<"\n";
if(!dir){
while(nowl>0&&pos-vec[nowl]<=vt){
pos-=vt;
nowl--;
cnt++;
}
pos=vec[nowl+1];
if(nowr>n){
if(nowl<1) flag=1;
break;
}
else if(vec[nowr]-pos<=vt*cnt){
cnt++;
pos=vec[nowr];
nowr++;
dir=!dir;
}
else{
break;
}
}
else{
while(nowr<=n&&vec[nowr]-pos<=vt){
pos+=vt;
nowr++;
cnt++;
}
pos=vec[nowr-1];
if(nowl<1){
if(nowr>n) flag=1;
break;
}
else if(pos-vec[nowl]<=vt*cnt){
cnt++;
pos=vec[nowl];
nowl--;
dir=!dir;
}
else{
break;
}
}
}
if(nowl<1&&nowr>n) flag=1;
}
}
if(flag) r=mid;
else l=mid+1;
}
cout<<l<<"\n";
}
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Incorrect | 1 ms | 344 KB | Output isn't correct |
| 2 | Halted | 0 ms | 0 KB | - |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Incorrect | 1 ms | 344 KB | Output isn't correct |
| 2 | Halted | 0 ms | 0 KB | - |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Incorrect | 1 ms | 344 KB | Output isn't correct |
| 2 | Halted | 0 ms | 0 KB | - |