Submission #321105

#	Time	Username	Problem	Language	Result	Execution time	Memory
321105		MetB	Gap (APIO16_gap)	C++14	90.00 / 100	83 ms	2020 KiB

gap

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

typedef long long ll;
typedef long double ld;

using namespace std;

ll findSmall(int N) {

	vector <ll> v (N);
	ll mn, mx;

	MinMax (1, 1e18, &mn, &mx);

	ll s = mn, e = mx;

	v[0] = s, v[N-1] = e;

	int l = 0, r = N - 1;

	while (l + 1 < r) {
		MinMax(v[l] + 1, v[r] - 1, &s, &e);
		v[++l] = s, v[--r] = e;
	}

	for (int i = 1; i < N; i++) {
		v[i-1] = v[i] - v[i-1];
	}

	return *max_element(v.begin(), v.end() - 1);
}

ll findGap(int T, int N) {

	if (T == 1) {
		return findSmall(N);
	}

	ll mn, mx;

	MinMax (1, 1e18, &mn, &mx);

	ll s = mn, e = mx;

	ld d = (ld) (mx - mn - 2) / N;

	ld l = mn + 1, r = mn + 1 + d;
	ll gap = 0, mx_old = mn;

	for (int i = 0; i < N - 1; i++) {
		ll il = ceil (l - 1e-7) + (ceil (l + 1e-7) == mx_old), ir = floor (r + 1e-7);
		//cout << il << ' ' << ir << endl;
		if (il > ir) continue;
		MinMax(il, ir, &mn, &mx);
		//cout << ' ' << mn << ' ' << mx << endl;
		if (mn != -1) {
			gap = max (gap, mn - mx_old);
			mx_old = mx;
		}
		l += d, r += d;
	}
	
	ll il = ceil (l - 1e-7) + (ceil (l + 1e-7) == mx_old), ir = floor (r + 1e-7);
	//cout << il << ' ' << ir << endl;

	
	if (il <= ir) MinMax(il, ir, &mn, &mx);
	//cout << ' ' << mn << ' ' << mx << endl;

	if (mn != -1 && il <= ir) {
		gap = max (gap, mn - mx_old);
		mx_old = mx;
	}

	gap = max (gap, e - mx_old);

	return gap;
}

Compilation message (stderr)

gap.cpp: In function 'll findGap(int, int)':
gap.cpp:44:5: warning: unused variable 's' [-Wunused-variable]
   44 |  ll s = mn, e = mx;
      |     ^

• Subtask 1: 30 / 30
• Subtask 2: 59.9997000019 / 70