标签:
Time Limit: 9000/4500 MS (Java/Others) Memory Limit: 131072/131072 K (Java/Others)
Total Submission(s): 849 Accepted Submission(s): 204

/*
hdu 5919 主席树(区间不同数的个数 + 区间第k大)
problem:
给你n个数字,和m个查询.
将[l,r]之间数第一次出现的位置信息弄成一个新的数组,然后找出其中k/2大的数.(k为位置的数量)
solve:
通过主席树能够找出[l,r]之间有多少个不同的数,然后利用再用一个查询找出第k大的即可.
(都是类似与线段树的操作, T[i]存的是[1,n]的信息, 尽管说的只是[i,n] ,只是[1,i-1]的还没更新而已. 所以查询的时候出了点问题)
hhh-2016-10-07 16:48:19
*/
#include <algorithm>
#include <iostream>
#include <cstdlib>
#include <stdio.h>
#include <cstring>
#include <vector>
#include <math.h>
#include <queue>
#include <set>
#include <map>
//#define lson i<<1
//#define rson i<<1|1
#define ll long long
#define clr(a,b) memset(a,b,sizeof(a))
using namespace std;
const int maxn = 200100;
const int N = maxn * 100;
template<class T> void read(T&num)
{
char CH;
bool F=false;
for(CH=getchar(); CH<‘0‘||CH>‘9‘; F= CH==‘-‘,CH=getchar());
for(num=0; CH>=‘0‘&&CH<=‘9‘; num=num*10+CH-‘0‘,CH=getchar());
F && (num=-num);
}
int stk[70], tp;
template<class T> inline void print(T p)
{
if(!p)
{
puts("0");
return;
}
while(p) stk[++ tp] = p%10, p/=10;
while(tp) putchar(stk[tp--] + ‘0‘);
putchar(‘\n‘);
}
int lson[N],rson[N],c[N];
int a[maxn],T[maxn];
int tot,n,m;
int build(int l,int r)
{
int root = tot++;
c[root ] = 0;
if(l != r)
{
int mid = (l+r)>>1;
lson[root] = build(l,mid);
rson[root] = build(mid+1,r);
}
return root;
}
int update(int root,int pos,int val)
{
int newroot = tot ++ ,tmp= newroot;
c[newroot] = c[root] + val;
int l = 1,r = n;
while(l < r)
{
int mid = (l + r) >> 1;
if(pos <= mid)
{
lson[newroot] = tot++;
rson[newroot] = rson[root];
newroot = lson[newroot] ;
root = lson[root];
r = mid;
}
else
{
lson[newroot] = lson[root],rson[newroot] = tot++;
newroot = rson[newroot],root = rson[root];
l = mid + 1;
}
c[newroot] = c[root] + val;
}
return tmp;
}
int query(int root,int pos)
{
int cnt = 0;
int l = 1,r = n;
while(pos < r)
{
int mid = (l + r) >> 1;
if(pos <= mid)
{
root = lson[root];
r = mid;
}
else
{
cnt += c[lson[root]];
root = rson[root];
l = mid + 1;
}
}
return cnt + c[root];
}
int Find(int root,int k)
{
int l = 1,r = n;
while(l <= r)
{
int mid = (l + r) >> 1;
if(l == r)
return l;
if(c[lson[root]] >= k)
{
root = lson[root];
r = mid;
}
else
{
k -= c[lson[root]];
root = rson[root];
l = mid +1 ;
}
}
}
int main()
{
int t,cas = 1;
// freopen("in.txt","r",stdin);
read(t);
while(t--)
{
tot = 0;
read(n),read(m);
for(int i = 1; i <= n; i++)
scanf("%d",&a[i]);
T[n + 1] = build(1,n);
map<int,int> mp;
for(int i = n; i >= 1; i--)
{
if(mp.find(a[i]) == mp.end())
{
T[i] = update(T[i + 1],i,1);
}
else
{
int tp = update(T[i+1],mp[a[i]],-1);
T[i] = update(tp,i,1);
}
mp[a[i]] = i;
}
int ans = 0;
int l,r;
printf("Case #%d:",cas++);
for(int i = 1; i <= m; i++)
{
read(l),read(r);
// cout << l <<" " <<r << endl;
l = (l + ans) % n + 1;
r = (r + ans)%n + 1;
if(l > r)
swap(l,r);
int num = (query(T[l],r)+1) >> 1;
// if(!num) num = 1;
ans = Find(T[l],num);
printf(" %d",ans);
}
printf("\n");
}
return 0;
}
hdu 5919 主席树(区间不同数的个数 + 区间第k大)
标签:
原文地址:http://www.cnblogs.com/Przz/p/5936266.html