Submission #1003117

#	Time	Username	Problem	Language	Result	Execution time	Memory
1003117		coolboy19521	Rice Hub (IOI11_ricehub)	C++17	0 / 100	2 ms	708 KiB

ricehub

#include "bits/stdc++.h"
#include "ricehub.h"
#define i64 long long

using namespace std;

const i64 sz = 2e5 + 10;

i64 a[sz];
i64 n;
i64 b;

bool che(i64 x) {
	i64 lra = x / 2;
	i64 rra = lra - !(x % 2);
	i64 ps = lra;
	i64 sm = 0;
	for (i64 i = 0; i < x; i ++) {
		sm += abs(a[i] - a[ps]);
	}
	// cout << x << ' ' << ps << ' ' << sm << '\n';
	if (sm <= b) {
		return true;
	}
	ps ++;
	for (; ps < n - rra; ps ++) {
		i64 pps = ps - 1; // previous ps
		sm -= abs(a[pps - lra] - a[pps]); // delete leftmost
		// if (0 < rra) { // if x is not 2
			sm -= abs(a[pps] - a[ps]); // delete new ps
			sm -= (rra - 1); // distance to right decreases
			sm += abs(a[ps + rra] - a[ps]); // add rightmost
		// }
		sm += abs(a[pps] - a[ps]); // add previous ps
		sm += (lra - 1); // distance to left increases
		// cout << x << ' ' << ps << ' ' << sm << '\n';
		if (sm <= b) {
			return true;
		}
	}
	return false;
}

int besthub(int R, int L, int X[], long long B)
{
	i64 le, ri;
	le = 0, ri = R + 1;

	for (i64 i = 0; i < R; i ++) {
		a[i] = X[i];
	}

	b = B;
	n = R;

	while (1 < ri - le) {
		i64 mi = le + (ri - le) / 2;

		if (che(mi)) {
			le = mi;
		} else {
			ri = mi;
		}
	}

	return le;
}

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