Submission #169098

#	Time	Username	Problem	Language	Result	Execution time	Memory
169098		mohammad_kilani	Aliens (IOI16_aliens)	C++17	4 / 100	2 ms	632 KiB

aliens

#include <bits/stdc++.h>
#include "aliens.h"
using namespace std;
const int N = 4010 , K = 4010;
vector< pair<int,int> > arr , tmp;
long long dp[N][K];
int n , m , k;

long long a[N] , b[N] , c[N] , tmpb[N];


long long tmp1;

int g;

inline long long get(long long a1,long long b1,long long a2,long long b2){
	tmp1 = (a1 - a2) / (b2 - b1) + 1;
	while(a1 * tmp1 + b1 > a2 * tmp1 + b2)
		tmp1--;
	tmp1 = max(tmp1 , 0LL);
	tmp1 = min(tmp1 , (long long)m);
	return tmp1;
}

long long take_photos(int n, int m, int k, std::vector<int> r, std::vector<int> c){
	for(int i = 0 ;i < n;i++){
		arr.push_back(make_pair(min(r[i] , c[i]) , -max(r[i] , c[i])));
	}
	sort(arr.begin(),arr.end());
	int mx = -1;
	for(int i = 0 ;i < (int)arr.size();i++){
		arr[i].second = -arr[i].second;
		if(arr[i].second > mx){
			tmp.push_back(arr[i]);
			mx = arr[i].second;
		}
	}
	arr = tmp;
	n = (int)arr.size();
	::n = n;
	::m = m;
	::k = k;
	for(int i = 0 ;i < n;i++){
		b[i] = (long long)(arr[i].second + 1) * (long long)(arr[i].second + 1);
		if(i < n - 1 && arr[i].second >= arr[i + 1].first)
			b[i] -= (long long)(arr[i].second - arr[i + 1].first + 1) * (long long)(arr[i].second - arr[i + 1].first + 1);
			a[i] = -2 * (long long)(arr[i].second + 1);
			c[i] = (long long)arr[i].first * (long long)arr[i].first;
	}
	for(int i = 0 ;i < n;i++){
		dp[i][k] = -(long long)1e18;
	}
	pair<int,int> tmp;
	for(int j = k - 1;j >= 0;j--){
		deque < pair<int,int> > q;
		for(int i = n - 1;i >= 0 ;i--){
			tmpb[i] = dp[i + 1][j + 1] + b[i];
			dp[i][j] = c[i] + a[i] * (long long)arr[i].first + tmpb[i];
			while((int)q.size() > 1){
				tmp = q.back();
				q.pop_back();
				if(q.back().first < arr[i].first){
					q.push_back(tmp);
					break;
				}
			}
			if((int)q.size() > 0){
				tmp = q.back();
				dp[i][j] = min(dp[i][j] , c[i] + a[tmp.second] * (long long)arr[i].first + tmpb[tmp.second]);
			}
			while((int)q.size() > 0){
				g = get(a[i] , tmpb[i] , a[q.front().second] , tmpb[q.front().second]);
				if(g >= q.front().first){
					q.pop_front();
					continue;
				}
				break;
			}
			if((int)q.size() == 0) g = m; else g = g = get(a[i] , tmpb[i] , a[q.front().second] , tmpb[q.front().second]);
			q.push_front(make_pair(g , i));
		}
	}
    return dp[0][0];
}

Compilation message (stderr)

aliens.cpp: In function 'long long int take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:45:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(i < n - 1 && arr[i].second >= arr[i + 1].first)
   ^~
aliens.cpp:47:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
    a[i] = -2 * (long long)(arr[i].second + 1);
    ^
aliens.cpp:79:41: warning: operation on 'g' may be undefined [-Wsequence-point]
    if((int)q.size() == 0) g = m; else g = g = get(a[i] , tmpb[i] , a[q.front().second] , tmpb[q.front().second]);
                                       ~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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