Submission #1297766

#TimeUsernameProblemLanguageResultExecution timeMemory
1297766hiepsimauhongAliens (IOI16_aliens)C++20
Compilation error
0 ms0 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){
                ary[i].fs = r[i - 1];
                ary[i].sd = c[i - 1];

                if(ary[i].fs > ary[i].sd) swap(a[i].fs, a[i].sd);
        }

        PreWork();
        return Caculate();
}

Compilation message (stderr)

aliens.cpp: In function 'Maxint take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:189:48: error: 'a' was not declared in this scope
  189 |                 if(ary[i].fs > ary[i].sd) swap(a[i].fs, a[i].sd);
      |                                                ^
aliens.h:1:9: warning: #pragma once in main file
    1 | #pragma once
      |         ^~~~
aliens_c.h:1:9: warning: #pragma once in main file
    1 | #pragma once
      |         ^~~~