| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1297765 | hiepsimauhong | Aliens (IOI16_aliens) | C++20 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
#include "aliens.h"
using namespace std;
//#define int long long
using Maxint = long long;
#define FOR(I, L, R) for(int I(L) ; I <= (int)R ; ++I)
#define FOD(I, R, L) for(int I(R) ; I >= (int)L ; --I)
#define FOA(I, A) for(auto &I : A)
#define print(A,L,R) FOR(OK, L, R){if(abs(A[OK]) >= oo / 10)cout<<"- ";else cout<<A[OK]<<' ';}cout<<'\n';
#define prints(A) FOA(OK, A){cout<<OK<<' ';}cout << '\n';
#define printz(A,L,R) FOR(OK, 0, L){FOR(KO, 0, R){if(abs(A[OK][KO]) <= oo / 10)cout<<A[OK][KO]<<' ';else cout << "- ";} cout << '\n';}cout << '\n';
#define fs first
#define sd second
#define ii pair<Maxint, Maxint>
#define iii pair<Maxint, ii>
#define all(A) A.begin(), A.end()
#define quickly ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define FILE "BUFF"
const int N = 4000 + 5;
const int mod = 1e9 + 7;
const Maxint oo = 1e18;
int n, m, k;
ii ary[N], rl[N];
int add[N], cost[N], f[N];
Maxint dp[N][N];
void init(){
cin >> n >> m >> k;
FOR(i, 1, n){
cin >> ary[i].fs;
}
FOR(i, 1, n){
cin >> ary[i].sd;
if(ary[i].fs > ary[i].sd) swap(ary[i].fs, ary[i].sd);
}
}
void PreWork(){
sort(ary + 1, ary + 1 + n, [&](ii &u, ii &v){
if(u.sd == v.sd){
return u.fs > v.fs;
}
return u.sd < v.sd;
});
stack<int> st;
FOR(i, 1, n){
while(!st.empty() && ary[st.top()].fs >= ary[i].fs){
add[i] += add[st.top()];
st.pop();
}
add[i]++;
st.push(i);
}
n = 0;
while(!st.empty()){
rl[++n] = ary[st.top()];
f[n] = add[st.top()];
st.pop();
}
reverse(rl + 1, rl + 1 + n);
reverse(f + 1, f + 1 + n);
FOR(i, 2, n){
int x = rl[i].fs;
int y = rl[i - 1].sd;
if(x <= y){
cost[i] = (y - x + 1) * (y - x + 1);
}
}
}
ii compare(ii u, ii v){
if(u.fs == v.fs){
return {u.fs, max(u.sd, v.sd)};
}
return min(u, v);
}
struct line{
Maxint a, b;
line(){a = b = 0;}
line(Maxint _a, Maxint _b){a = _a, b = _b;}
Maxint eval(int x){ return a * x + b; }
long double operator & (const line &other) const{
return (long double)(other.b - b) / (a - other.a);
}
};
struct ConvexHullTrick{
vector<line> hull;
bool bad(line &L1, line &L2, line &L3){
return (L1 & L2) >= (L1 & L3);
}
void add_line(line L){
while(hull.size() >= 2){
if(bad(hull.back(), hull[hull.size() - 2], L)){
hull.pop_back();
}
else{
break;
}
}
hull.push_back(L);
}
Maxint get(Maxint x){
int l = 0, r = hull.size() - 2;
int res = 0;
while(l <= r){
int mid = (l + r) >> 1;
if(hull[mid].eval(x) <= hull[mid + 1].eval(x)){
r = mid - 1;
res = mid;
}
else{
l = mid + 1;
}
}
if(hull.size() == 1) return hull[0].eval(x);
return min(hull[res].eval(x), hull[res + 1].eval(x));
}
} cht;
Maxint Caculate(){
memset(dp, 0x3f, sizeof dp);
dp[0][0] = 0;
FOR(h, 1, min(k, n)){
cht.hull.clear();
FOR(i, 1, n){
int x = rl[i].fs;
int y = rl[i].sd + 1;
if(dp[h - 1][i - 1] < oo){
cht.add_line(line(-2 * x, x * x + dp[h - 1][i - 1] - cost[i]));
}
dp[h][i] = cht.get(y) + y * y;
}
}
Maxint ans = oo;
FOR(i, 1, k){
ans = min(ans, dp[i][n]);
}
return ans;
}
/*signed main(){ quickly
if(fopen(FILE".inp", "r")){
freopen(FILE".inp", "r", stdin);
freopen(FILE".out", "w", stdout);
}
init();
PreWork();
cout << Caculate();
}*/
Maxint take_photos(int _n, int _m, int _k, vector<int> r, vector<int> c){
n = _n;
m = _m;
k = _k;
FOR(i, 1, n){
a[i].fs = r[i - 1];
a[i].sd = c[i - 1];
if(a[i].fs > a[i].sd) swap(a[i].fs, a[i].sd);
}
PreWork();
return Caculate();
}