| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 144420 | liwi | Aliens (IOI16_aliens) | C++11 | 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>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
#define scan(x) do{while((x=getchar())<'0'); for(x-='0'; '0'<=(_=getchar()); x=(x<<3)+(x<<1)+_-'0');}while(0)
char _;
#define complete_unique(a) a.erase(unique(a.begin(),a.end()),a.end())
#define all(a) a.begin(),a.end()
#define println printf("\n");
#define readln(x) getline(cin,x);
#define pb push_back
#define endl "\n"
#define INT_INF 0x3f3f3f3f
#define LL_INF 0x3f3f3f3f3f3f3f3f
#define MOD 1000000007
#define MOD2 1190492669
#define SEED 131
#define mp make_pair
#define fastio cin.tie(0); cin.sync_with_stdio(0);
#define MAXN 105
#define MAXK 105
typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
typedef unordered_map<int,int> umii;
typedef pair<int,int> pii;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef pair<int,pii> triple;
typedef int8_t byte;
mt19937 g1(time(0));
int randint(int a, int b){return uniform_int_distribution<int>(a, b)(g1);}
ll randlong(ll a,ll b){return uniform_int_distribution<long long>(a, b)(g1);}
ll gcd(ll a, ll b){return b == 0 ? a : gcd(b, a % b);}
ll lcm(ll a, ll b){return a*b/gcd(a,b);}
ll fpow(ll b, ll exp, ll mod){if(exp == 0) return 1;ll t = fpow(b,exp/2,mod);if(exp&1) return t*t%mod*b%mod;return t*t%mod;}
ll divmod(ll i, ll j, ll mod){i%=mod,j%=mod;return i*fpow(j,mod-2,mod)%mod;}
int num_points,len,num_photo,ptr,cnt[MAXN];
pii points[MAXN],p[MAXN],lst;
ll dp[MAXN][MAXK],m[MAXN],ndp[MAXN];
inline bool cmp(pii &a, pii &b){
if(a.first == b.first) return a.second>b.second;
return a.first<b.first;
}
inline ll calc(int k, int i, int j){
ll c1 = dp[k-1][j]+1LL*(p[i].second-p[j+1].first+1)*(p[i].second-p[j+1].first+1);
ll c2 = m[j]*m[j];
return c1-c2;
}
inline ld inter(int j, int k, int g){
ll m1 = -2LL*(p[j+1].first-1), b1 = 1LL*(p[j+1].first-1)*(p[j+1].first-1)+dp[g-1][j]-m[j]*m[j];
ll m2 = -2LL*(p[k+1].first-1), b2 = 1LL*(p[k+1].first-1)*(p[k+1].first-1)+dp[g-1][k]-m[k]*m[k];
return (ld)(b2-b1)/(m1-m2);
}
ll take_photos(int nn, int mm, int kk, int rows[MAXN], int cols[MAXN]){
num_points = nn, len = mm, num_photo = kk, ptr = 0;
for(int i=1; i<=num_points; i++){
int a = min(rows[i-1],cols[i-1]);
int b = max(rows[i-1],cols[i-1]);
points[i] = mp(a,b);
}
sort(points+1,points+num_points+1,cmp);
lst = p[++ptr] = points[1], p[0] = mp(-1,-1);
for(int i=2; i<=num_points; i++){
int r = points[i].second;
if(r > lst.second){
p[++ptr] = points[i];
lst = points[i];
}
}
for(int i=1; i<ptr; i++)
m[i] = max(0,p[i].second-p[i+1].first+1);
memset(dp,0x3f,sizeof dp);
dp[0][0] = 0;
for(int k=1; k<=num_photo; k++){
deque<int> dq; dq.pb(0);
// for(int i=0; i<=ptr; i++){
// if(dp[k-1][i] == LL_INF) continue;
// while(dq.size() >= 2 && inter(dq[dq.size()-2],i,k) <= inter(dq[dq.size()-2],dq.back(),k)) dq.pop_back();
// dq.pb(i);
// }
//dp[k][i] = max(dp[k-1][v]+(p[i]-(p[v+1]-1))*(p[i]-(p[v+1]-1))-m[v]*m[v]
//dp[k][i] = dp[k-1][v]+p[i]^2-2*p[i]*(p[v+1]-1)+(p[v+1]-1)^2-m[v]^2
//dp[k][i] = -2*(p[v+1]-1)*p[i]+(p[v+1]-1)^2+dp[k-1][v]-m[v]^2
//m = -2*(p[v+1]-1);
//b = (p[v+1]-1)^2+dp[k-1][v]-m[v]^2
dp[k][0] = 0;
for(int i=1; i<=ptr; i++){
while(dq.size() >= 2 && calc(k,i,dq[0]) >= calc(k,i,dq[1])) dq.pop_front();
dp[k][i] = calc(k,i,dq[0]);
if(dp[k-1][i] != LL_INF){
while(dq.size() >= 2 && inter(dq[dq.size()-2],i,k) <= inter(dq[dq.size()-2],dq.back(),k)) dq.pop_back();
dq.pb(i);
}
// for(int v=i-1; v>=0; v--){
// ll cost = dp[k-1][v]+1LL*(p[i].second-p[v+1].first+1)*(p[i].second-p[v+1].first+1);
// ll overlap = m[v]*m[v];
// dp[k][i] = min(dp[k][i],cost-overlap);
// }
}
}
return dp[num_photo][ptr];
}
int main(){
int r[MAXN] = {0,4,4,4,4};
int c[MAXN] = {3,4,6,5,6};
printf("%lld\n",take_photos(5,7,2,r,c));
r[0] = 1, r[1] = 0, r[2] = 2, r[3] = 2;
c[0] = 3, c[1] = 1, c[2] = 1, c[3] = 2;
printf("%lld\n",take_photos(4,4,4,r,c));
}
/*
4 4 4
1 3
0 1
2 1
2 2
ans=12
*/