#include<cstdio>
#include<iostream>
using namespace std;
const int N = 1e6;
int n , y[N + 5] , m , k , Min[N + 5][23] , Max[N + 5][23] , ans;
inline void prepare()
{
for(register int j = 1; (1 << j) <= n; j++)
for(register int i = 1; i + (1 << j) - 1 <= n; i++)
{
Min[i][j] = min(Min[i][j - 1] , Min[i + (1 << j - 1)][j - 1]);
Max[i][j] = max(Max[i][j - 1] , Max[i + (1 << j - 1)][j - 1]);
}
}
inline bool check(int mid , int m)
{
int l = 1;
for(register int i = 1; i <= m && l <= n; i++)
{
int r = l , smin = y[l] , smax = y[l];
for(register int j = 22;j >= 0; j--)
if (r + (1 << j) <= n)
{
int tmin = Min[r + 1][j] , tmax = Max[r + 1][j];
if (max(smax , tmax) - min(smin , tmin) <= mid)
{
r += (1 << j);
smax = max(smax , tmax);
smin = min(smin , tmin);
}
}
l = r + 1;
}
return l > n;
}
inline int work(int m)
{
int res , l = 0 , r = 1e9 , mid;
while (l <= r)
{
mid = (l + r) >> 1;
if (check(mid , m)) res = mid , r = mid - 1;
else l = mid + 1;
}
return res;
}
int main()
{
// freopen("a.in" , "r" , stdin);
scanf("%d" , &n);
for(register int i = 1; i <= n; i++)
{
scanf("%*d%d" , &y[i]);
Min[i][0] = Max[i][0] = y[i];
}
prepare();
scanf("%d" , &k);
while (k--)
{
scanf("%d" , &m);
ans = work(m);
if (ans & 1) printf("%.1lf\n" , ans * 1.0 / 2);
else printf("%d\n" , ans / 2);
}
}
原文:https://www.cnblogs.com/leiyuanze/p/12346523.html