Submission #207538

#	Time	Username	Problem	Language	Result	Execution time	Memory
207538		robs	Rice Hub (IOI11_ricehub)	C++17	68 / 100	22 ms	1528 KiB

ricehub

#include "ricehub.h"
#include <bits/stdc++.h>
#define debug(args...) //fprintf(stderr, args)
typedef long long int lli;
using namespace std;
const int maxn = 2e5;
int s[maxn],cs[maxn],I,J,SUM;

int besthub(int R, int L, int X[], long long int B)
{
	s[0] = X[0];
	// debug("R-1 = %d\n",R-1);
	for(int x = 1; x < R; x++)
		s[x] = s[x-1] + X[x];
	for(int x = 0; x < R; x++)
		// debug("s[%d] = %d | d = %d\n",x,s[x],X[x]);
	cs[R-1] = 0;
	// debug("\n");
	for(int x = R-2; x >= 0; x--)
		cs[x] = cs[x+1] + X[R-1] - X[x];
	// for(int x = 0; x < R; x++)
		// debug("cs[%d] = %d | d = %d\n",x,cs[x],X[R-1]-X[x]);
	// debug("\n\n");
	int i = 0;
	int j = 0;
	lli resp = 0;
	while(j < R)
	{
		int med = (i + j) / 2;
		lli sumEsq = (cs[i] - cs[med]) - ((med - i)*(X[R-1] - X[med]));
		// debug("%d - %d:\nsumEsq = %d = (%d-%d) - ((%d-%d)*(%d-%d))\n",i,j,sumEsq,cs[i],cs[med],med,i,X[R-1],X[med]);
		lli sumDir = (s[j] - s[med]) - ((j - med)*X[med]);
		// debug("sumDir = %d = (%d-%d) - ((%d-%d)*(%d-%d))\n",sumDir,s[j],s[med],j,med,X[med],X[0]);
		lli sum = sumEsq + sumDir;
		lli r = j - i + 1;
		// debug("%d - %d(%d)	%d  %d 		-%d-\n\n",i,j,sum,sumEsq,sumDir,med);
		if(sum <= B)
		{
			resp = max(resp, r);
			j++;
		}
		else if(i == j)
		{
			j++;
		}
		else	i++;
	}
	return resp;
}

• Subtask 1: 17 / 17
• Subtask 2: 25 / 25
• Subtask 3: 26 / 26
• Subtask 4: 0 / 32