#include "gap.h"
#include <bits/stdc++.h>
using ll = long long;
ll gMaxDiff = 0;
void maxDiff(ll min, ll max)
{
ll mid = min + (max - min) / 2;
ll s1Min, s1Max;
MinMax(min + 1, mid, &s1Min, &s1Max);
bool s1Pop = s1Min != -1;
ll s2Min, s2Max;
MinMax(mid + 1, max - 1, &s2Min, &s2Max);
bool s2Pop = s2Min != -1;
if (s1Pop && s2Pop)
{
gMaxDiff = std::max(gMaxDiff, s2Min - s1Max);
gMaxDiff = std::max(gMaxDiff, s1Min - min);
gMaxDiff = std::max(gMaxDiff, max - s2Max);
}
else if (!s1Pop && s2Pop)
{
gMaxDiff = std::max(gMaxDiff, s2Min - min);
gMaxDiff = std::max(gMaxDiff, max - s2Max);
}
else if (s1Pop && !s2Pop)
{
gMaxDiff = std::max(gMaxDiff, s1Min - min);
gMaxDiff = std::max(gMaxDiff, max - s1Max);
}
else if (!s1Pop && !s2Pop)
{
gMaxDiff = std::max(gMaxDiff, max - min);
}
if (s1Pop && s1Max - s1Min > gMaxDiff)
maxDiff(s1Min, s1Max);
if (s2Pop && s2Max - s2Min > gMaxDiff)
maxDiff(s2Min, s2Max);
}
long long findGap(int T, int N)
{
ll min, max;
MinMax(0, 1000000000000000000, &min, &max);
maxDiff(min, max);
return gMaxDiff;
}
