AcWing 143. 最大异或对
原题链接
简单
作者:
大风大雪
,
2021-02-11 14:56:42
,
所有人可见
,
阅读 285
#include <iostream>
#include <algorithm>
using namespace std;
const int N = 100010, M = N * 31;
int n;
int a[N], son[M][2], idx;
void insert(int x)
{
int p = 0;
for (int i = 30; i >= 0; i -- )
{
int u = x >> i & 1;
if (!son[p][u]) son[p][u] = ++ idx;
p = son[p][u];
}
}
int search(int x)
{
int p = 0, res = 0;
for (int i = 30; i >= 0; i -- )
{
int s = x >> i & 1;
if (son[p][!s])
{
res |= 1 << i;
p = son[p][!s];
}
else p = son[p][s];
}
return res;
}
int main()
{
scanf("%d", &n);
for (int i = 0; i < n; i ++ )
{
scanf("%d", &a[i]);
insert(a[i]);
}
int res = 0;
for (int i = 0; i < n; i ++ ) res = max(res, search(a[i]));
printf("%d\n", res);
return 0;
}