Submission #108200

#	Time	Username	Problem	Language	Result	Execution time	Memory
108200		luciocf	Gap (APIO16_gap)	C++14	30 / 100	241 ms	1916 KiB

gap

#include <bits/stdc++.h>
#include "gap.h"

using namespace std;

const int maxn = 1e5+10;
const long long maxv = 1e18;

typedef long long ll;

ll a[maxn];

long long findGap(int T, int N)
{
	if (T == 1)
	{
		ll mn, mx;
		MinMax(0, maxv, &mn, &mx);

		int l = 1, r = N;
		a[1] = mn, a[N] = mx;

		while (true)
		{
			if (r-l <= 1) break;

			MinMax(a[l]+1, a[r]-1, &mn, &mx);

			a[++l] = mn, a[--r] = mx;
		}

		ll ans = 0;
		for (int i = 1; i < N; i++)
			ans = max(ans, a[i+1]-a[i]);

		return ans;
	}

	ll s = 0, mn, mx, last;
	ll ans = 0;

	MinMax(0, maxv, &mn, &mx);

	s = mn, last = mx;

	while (true)
	{
		mn = mx = -1;

		int ini = 0, fim = 60, k;
		while (ini <= fim)
		{
			int mid = (ini+fim)>>1;

			ll t = s+(1LL<<mid);

			MinMax(s+1, t, &mn, &mx);

			if (mn != -1 && mx != -1) k = mid, fim = mid-1;
			else ini = mid+1;
		}

		MinMax(s+1, s+(1LL<<k), &mn, &mx);

		ans = max(ans, mn-s);

		s = mx;
		if (s >= last) break;
	}

	return ans;
}

Compilation message (stderr)

gap.cpp: In function 'long long int findGap(int, int)':
gap.cpp:63:21: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
   MinMax(s+1, s+(1LL<<k), &mn, &mx);
                 ~~~~^~~~

• Subtask 1: 30 / 30
• Subtask 2: 0 / 70