| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 601370 | alexander707070 | The short shank; Redemption (BOI21_prison) | C++14 | 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<bits/stdc++.h>
#define MAXN 2000007
using namespace std;
const long long inf=1e16;
int n,d;
long long t,a[MAXN];
long long cost[MAXN][MAXN],mins;
long long dp[MAXN][2];
void solve(int l,int r,int optl,int optr,int k){
if(l>r)return;
int mid=(l+r)/2,opt=0;
dp[mid][k%2]=inf;
for(int i=optl;i<=min(optr,mid);i++){
if(dp[i-1][(k-1)%2]+cost[i][mid]<dp[mid][k%2]){
dp[mid][k%2]=dp[i-1][(k-1)%2]+cost[i][mid];
opt=i;
}
}
solve(l,mid-1,optl,opt,k);
solve(mid+1,r,opt,optr,k);
}
int main(){
cin>>n>>d>>t;
for(int i=1;i<=n;i++){
cin>>a[i];
}
for(int i=1;i<=n;i++){
mins=inf;
for(int f=i;f<=n;f++){
cost[i][f]=cost[i][f-1];
if(min(a[f],f+mins)<=t)cost[i][f]++;
mins=min(mins,a[f]-f);
}
}
dp[0][0]=0;
for(int i=1;i<=n;i++){
dp[i][0]=inf;
}
for(int i=1;i<=d+1;i++){
dp[0][i%2]=inf;
solve(1,n,1,n,i);
}
cout<<dp[n][(d+1)%2]<<"\n";
return 0;
}