Submission #337597

#	Time	Username	Problem	Language	Result	Execution time	Memory
337597		errorgorn	Aliens (IOI16_aliens)	C++17	25 / 100	2073 ms	1516 KiB

aliens

//雪花飄飄北風嘯嘯
//天地一片蒼茫

#include "aliens.h"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
#define ll long long
#define ii pair<ll,ll>
#define iii pair<ii,ll>
#define fi first
#define se second
#define endl '\n'
#define debug(x) cout << #x << " is " << x << endl

#define rep(x,start,end) for(auto x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)(x).size()

#define indexed_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>
//change less to less_equal for non distinct pbds, but erase will bug

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

int n,m,k;
vector<ii> v;
ll extra[100005];
ll memo[2][50005];

ll sq(ll i){return i*i;}

long long take_photos(int N, int M, int K, std::vector<int> R, std::vector<int> C) {
    n=N,m=M,k=K;
    
    rep(x,0,n){
		int a=R[x],b=C[x];
		if (a>b) swap(a,b);
		v.push_back(ii(a,b+1));
	}
	
	sort(all(v),[](ii i,ii j){
		if (i.fi!=j.fi) return i.fi<j.fi;
		else return i.se>j.se;
	});
	
	vector<ii> temp;
	for (auto &it:v){
		if (temp.empty() || temp.back().se<it.se) temp.push_back(it);
	}
	
	swap(v,temp);
	
	//for (auto &it:v) cout<<it.fi<<" "<<it.se<<endl;
	
	rep(x,1,sz(v)) extra[x]=sq(max(0LL,v[x-1].se-v[x].fi));
	//rep(x,0,sz(v)) cout<<extra[x]<<" "; cout<<endl;
	
	int a=0,b=1;
	memset(memo,63,sizeof(memo));
	
	rep(x,0,k){
		memo[a][0]=0;
		memset(memo[b],63,sizeof(memo[b]));
		
		rep(y,0,sz(v)){
			rep(z,y,sz(v)){
				memo[b][z+1]=min(memo[b][z+1],memo[a][y]-extra[y]+sq(v[z].se-v[y].fi));
			}
		}
		swap(a,b);
	}
	
	return memo[a][sz(v)];
}

• Subtask 1: 4 / 4
• Subtask 2: 12 / 12
• Subtask 3: 9 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 40