| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 313225 | AmineWeslati | Boxes with souvenirs (IOI15_boxes) | 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.
//Never stop trying
//#include "boxes.h"
#include <bits/stdc++.h>
using namespace std;
#define boost ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
typedef string str;
typedef long long ll;
typedef double db;
typedef long double ld;
typedef pair<int, int> pi;
#define fi first
#define se second
typedef vector<int> vi;
typedef vector<pi> vpi;
typedef vector<str> vs;
typedef vector<ld> vd;
#define pb push_back
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define endl "\n"
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
const int MOD = 1e9 + 7; //998244353
const ll INF = 1e18;
const int MX = 2e5 + 10;
const int nx[4] = {0, 0, 1, -1}, ny[4] = {1, -1, 0, 0}; //right left down up
template<class T> using V = vector<T>;
template<class T> bool ckmin(T& a, const T& b) { return a > b ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
ll cdiv(ll a, ll b) { return a / b + ((a ^ b) > 0 && a % b); } // divide a by b rounded up
constexpr int log2(int x) { return 31 - __builtin_clz(x); } // floor(log2(x))
#define dbg(x) cerr << " - " << #x << " : " << x << endl;
#define dbgs(x,y) cerr << " - " << #x << " : " << x << " / " << #y << " : " << y << endl;
#define dbgv(v) cerr << " - " << #v << " : " << endl << "[ "; for(auto it : v) cerr << it << ' '; cerr << ']' << endl;
void IO() {
#ifndef ONLINE_JUDGE
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
}
/*ll solve(int d,int i){
if(pos[i]==0) return 0;
if(d==1){
ll ans=0;
while(i>=0){
ll x=pos[i];
x+=min(pos[i],L-pos[i]);
ans+=x;
i-=K;
}
return ans;
}
else{
ll ans=0;
while(i<sz(pos)){
ll x=L-pos[i];
x+=min(pos[i],L-pos[i]);
ans+=x;
i+=K;
}
return ans;
}
}
*/
int N,K,L;
vi pos;
ll memo[1005][1005];
ll solve(int l, int r){
if(l>r) return 0;
if(memo[l][r]!=-1) return memo[l][r];
ll ans=INF;
int ll=1,rr=K;
int k;
//max k st l and l+k same side
/*while(ll<=rr){
int m=(ll+rr)/2;
if(min( (L-pos[l])*2,pos[min(N-1,l+m)]*2 )<=L){
k=m;
ll=m+1;
}
else rr=m-1;
}*/
FOR(k,1,K+1){
int nr=l+k-1; if(nr>r) break;
ckmin(ans,solve(nr+1,r)+
min(L, min( (L-pos[l])*2,pos[nr]*2 ) ));
/*ll=1,rr=K;
//max k st r and r-k same side
while(ll<=rr){
int m=(ll+rr)/2;
if(min( (L-pos[max(0,r-m)])*2,pos[r]*2 )<=L){
k=m;
ll=m+1;
}
else rr=m-1;
}*/
}
FOR(k,1,K+1){
int nl=r-k+1; if(nl<l) break;
ckmin(ans,solve(l,nl-1)+
min(L, min( (L-pos[nl])*2,pos[r]*2 ) ));
}
return memo[l][r]=ans;
}
ll delivery(int NN, int KK, int LL, int positions[]){
N=NN; K=KK; L=LL; FOR(i,0,N) pos.pb(positions[i]);
pos.pb(0); N++;
sort(all(pos));
if(K==1){
ll ans=0;
for(auto x: pos){ans+=(min(L-x,x))*2;}
return ans;
}
if(K==N-1){
ll ans=L;
FOR(i,0,sz(pos)){
ll x=pos[i]*2;
if(i+1<sz(pos)) x+=(ll)(L-pos[i+1])*2;
ckmin(ans,x);
}
return ans;
}
FOR(i,0,N) FOR(j,0,N) memo[i][j]=-1;
return solve(0,N-1);
}
int main() {
boost; IO();
int N,K,L; cin>>N>>K>>L;
int pos[N];
FOR(i,0,N) cin>>pos[i];
cout << delivery(N,K,L,pos) << endl;
return 0;
}
/*
3 2 8
1 2 5
*/
/* Careful!!!
.Array bounds
.Infinite loops
.Uninitialized variables / empty containers
.Order of input
Some insights:
.Binary search
.Graph representation
.Write brute force code
.Change your approach
*/