线段树(区间维护)：HDU 3308 LCIS

LCIS

Time Limit: 6000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 5951    Accepted Submission(s): 2578

Problem Description

Given n integers.
You have two operations:
U A B: replace the Ath number by B. (index counting from 0)
Q A B: output the length of the longest consecutive increasing subsequence (LCIS) in [a, b].

 

Input

T in the first line, indicating the case number.
Each case starts with two integers n , m(0<n,m<=10⁵).
The next line has n integers(0<=val<=10⁵).
The next m lines each has an operation:
U A B(0<=A,n , 0<=B=10⁵)
OR
Q A B(0<=A<=B< n).

 

Output

For each Q, output the answer.

 

Sample Input

1 10 10 7 7 3 3 5 9 9 8 1 8 Q 6 6 U 3 4 Q 0 1 Q 0 5 Q 4 7 Q 3 5 Q 0 2 Q 4 6 U 6 10 Q 0 9

 

Sample Output

1 1 4 2 3 1 2 5

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;
const int maxn=100010;
int T[maxn<<2],L[maxn<<2],R[maxn<<2],ar[maxn],n,m;

void Updata(int node,int l,int r)
{    
    int mid=(l+r)>>1,a=node<<1,b=a|1;

    L[node]=L[a];
    if(L[a]==mid-l+1&&ar[mid]<ar[mid+1])
        L[node]+=L[b];
    
    R[node]=R[b];
    if(R[b]==r-mid&&ar[mid]<ar[mid+1])
        R[node]+=R[a];
    
    T[node]=max(T[a],T[b]);
    if(ar[mid]<ar[mid+1])
        T[node]=max(T[node],R[a]+L[b]);
}

void Change(int node,int l,int r,int pos,int x)
{
    if(l==r){
        T[node]=L[node]=R[node]=1;
        ar[pos]=x;
        return;
    }
    int mid=(l+r)>>1;
    if(mid>=pos)
        Change(node<<1,l,mid,pos,x);
    else
        Change(node<<1|1,mid+1,r,pos,x);
    Updata(node,l,r);    
}
int ans;

int Query(int node,int l,int r,int a,int b)
{
    if(l>=a&&r<=b)
        return T[node];
    int mid=(l+r)>>1;
    int ret=0;
    if(a<=mid)
        ret=Query(node<<1,l,mid,a,b);
    if(b>mid)
        ret=max(ret,Query(node<<1|1,mid+1,r,a,b));
    if(a<=mid&&b>mid&&ar[mid]<ar[mid+1])
        ret=max(ret,min(R[node<<1],mid-a+1)+min(L[node<<1|1],b-mid));
    return ret;
}            
int main()    
{                
    int Tk,a,b;        
    char s[5];        
    scanf("%d",&Tk);    
    while(Tk--)        
    {                        
        scanf("%d%d",&n,&m);
        memset(L,0,sizeof(L));
        memset(R,0,sizeof(R));
        memset(T,0,sizeof(T));
        
        for(int i=1;i<=n;i++){
            scanf("%d",&ar[i]);
            Change(1,1,n,i,ar[i]);
        }
        while(m--){                    
            scanf("%s",s);                
            scanf("%d%d",&a,&b);            
            if(s[0]=='U')                
                Change(1,1,n,a+1,b);            
            else{                                                        
                printf("%d
",Query(1,1,n,a+1,b+1));            
            }                        
        }                                
    }                
    return 0;
}