hdu 3308 LCIS (线段树单点更新)

#include <iostream>
#include <cstdio>
#include <algorithm>
#define lson num<<1,s,mid
#define rson num<<1|1,mid+1,e
#define maxn 100005
using namespace std;

int lem[maxn<<2];
int rim[maxn<<2];
int tre[maxn<<2];//最大连续递增区间
int lez[maxn<<2];//区间左端点的值
int riz[maxn<<2];//----右--------

void pushup(int num,int s,int e)
{
    int mid=(s+e)>>1;

    lem[num]=lem[num<<1];
    rim[num]=rim[num<<1|1];
    lez[num]=lez[num<<1];
    riz[num]=riz[num<<1|1];
    if(lem[num]==mid-s+1)
    {
        if(riz[num<<1]<lez[num<<1|1])//注意一下这个判断就好
        lem[num]+=lem[num<<1|1];
    }
    if(rim[num]==e-mid)
    {
        if(riz[num<<1]<lez[num<<1|1])
        rim[num]+=rim[num<<1];
    }
    int tmp=0;
    if(riz[num<<1]<lez[num<<1|1])
    tmp = rim[num<<1]+lem[num<<1|1];
    tre[num] = max(tmp,max(tre[num<<1],tre[num<<1|1]));
}
void debug(int num,int s,int e)//=。=  debug debug 多好的debug啊
{
    printf("s = %d,e = %d,lem = %d,rim = %d,tre = %d\n",s,e,lem[num],rim[num],tre[num]);
    if(s==e)return;
    int mid=(s+e)>>1;
    debug(lson);
    debug(rson);
}
void build(int num,int s,int e)
{
    if(s==e)
    {
        scanf("%d",&lez[num]);
        riz[num]=lez[num];
        lem[num]=rim[num]=tre[num]=1;
        return;
    }
    int mid=(s+e)>>1;
    build(lson);
    build(rson);
    pushup(num,s,e);
}

int query(int num,int s,int e,int l,int r)
{
    if(l<=s && r>=e)
    {
        return tre[num];
    }
    int mid=(s+e)>>1;
    if(r<=mid)return query(lson,l,r);
    else if(l>mid)return query(rson,l,r);
    else
    {
        int L=min(mid-l+1,rim[num<<1]);//这里也是比较不好想的
        int R=min(r-mid,lem[num<<1|1]);
        int tmp=0;
        if(riz[num<<1]<lez[num<<1|1])tmp=L+R;
        return max(tmp,max(query(lson,l,r),query(rson,l,r)));
    }
}
void update(int num,int s,int e,int pos,int val)
{
    if(s==e)
    {
        lez[num]=riz[num]=val;
        rim[num]=lem[num]=1;
        tre[num]=1;
        return;
    }
    int mid=(s+e)>>1;
    if(pos<=mid)update(lson,pos,val);
    else if(pos>mid)update(rson,pos,val);
    pushup(num,s,e);
}
int main()
{
    int T;
    int n,m;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d%d",&n,&m);
        build(1,1,n);
        //debug(1,1,n);
        while(m--)
        {
            char op[5];
            int a,b;
            scanf("%s%d%d",op,&a,&b);
            if(op[0]=='U')a++,update(1,1,n,a,b);
            else a++,b++,printf("%d\n",query(1,1,n,a,b));
        }
    }
    return 0;
}