Submission #347976

#	Time	Username	Problem	Language	Result	Execution time	Memory
347976		joylintp	Gap (APIO16_gap)	C++17	19.72 / 100	50 ms	1272 KiB

gap

#include "gap.h"
#include<bits/stdc++.h>
using namespace std;
 
long long ans = 0;
 
long long dfs(long long l, long long r)
{
    if (r - l <= ans)
        return ans;
 
    if (r - l <= 1)
        return ans = max(ans, r - l);
 
    if (r - l == 2)
    {
        long long tl, tr;
        MinMax(l, l + 1, &tl, &tr);
        if (tr == l + 1)
            return ans = max(ans, 1LL);
        else
            return ans = max(ans, 2LL);
    }
  
    if (r - l == 3)
    {
        long long tl, tr;
        MinMax(l + 1, r - 1, &tl, &tr);
        if (tl == l + 1 && tr == r - 1)
            return ans = max(ans, 1LL);
        else if (tl == l + 1 || tr == r - 1)
            return ans = max(ans, 2LL);
        else
            return ans = max(ans, 3LL);
    }
 
    long long m = (l + r) / 2, ll, lr, rl, rr;
    MinMax(l + 1, m, &ll, &lr), MinMax(m + 1, r - 1, &rl, &rr);
 
    long long ret = ans;
    if (ll == -1 && rr == -1)
        ret = r - l;
    else if (ll == -1)
    {
        ret = max({ret, rl - l, r - rr});
        if (rr - rl > ret)
            ret = max(ret, dfs(rl, rr));
    }
    else if (rr == -1)
    {
        ret = max({ret, ll - l, r - lr});
        if (lr - ll > ret)
            ret = max(ret, dfs(ll, lr));
    }
    else
    {
        ret = max({ret, ll - l, rl - lr, r - rr});
        if (lr - ll > ret)
            ret = max(ret, dfs(ll, lr));
        if (rr - rl > ret)
            ret = max(ret, dfs(rl, rr));
    }
    return ans = max(ans, ret);
}
 
long long findGap(int T, int N)
{
    long long l, r;
    MinMax(0, 1000000000000000000, &l, &r);
	return dfs(l, r);
}

• Subtask 1: 0 / 30
• Subtask 2: 19.7180885677 / 70