hdu5306(線段樹＋區間取最值)

題目鏈接：http://acm.hdu.edu.cn/showproblem.php?pid=5306

思路：這是１６年國家集訓隊jls的論文

#include <cstdio>
#include <cstdlib>
#include <cassert>
#include <cstring>
#include <bitset>
#include <cmath>
#include <cctype>
#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <queue>
#include <map>
#include <set>
#include <sstream>
#include <iomanip>
using namespace std;
typedef long long ll;
typedef vector<long long> VI;
typedef unsigned long long ull;
const ll inff = 0x3f3f3f3f3f3f3f3f;
#define FOR(i,a,b) for(int i(a);i<=(b);++i)
#define FOL(i,a,b) for(int i(a);i>=(b);--i)
#define SZ(x) ((long long)(x).size())
#define REW(a,b) memset(a,b,sizeof(a))
#define inf int(0x3f3f3f3f)
#define si(a) scanf("%d",&a)
#define sl(a) scanf("%lld",&a)
#define sd(a) scanf("%lf",&a)
#define ss(a) scanf("%s",a)
#define mod ll(1e9+7)
#define pb push_back
#define eps 1e-6
#define lc d<<1
#define rc d<<1|1
#define Pll pair<ll,ll>
#define P pair<int,int>
#define pi acos(-1)
int n,m,a[1000008],x,y,t,op,z;
struct as{
    int l,r,ma,maa,num,lz;
    ll su;
}tr[1000008<<2];
inline int read()
{
    int X=0,w=0; char ch=0;
    while(!isdigit(ch)) {w|=ch=='-';ch=getchar();}
    while(isdigit(ch)) X=(X<<3)+(X<<1)+(ch^48),ch=getchar();
    return w?-X:X;
}
void push(int d)
{
    tr[d].su=tr[lc].su+tr[rc].su;tr[d].num=0;
    tr[d].ma=max(tr[lc].ma,tr[rc].ma);
    tr[d].maa=max(tr[lc].maa,tr[rc].maa);
    if(tr[lc].ma!=tr[rc].ma) tr[d].maa=max(tr[d].maa,min(tr[lc].ma,tr[rc].ma));
    if(tr[d].ma==tr[lc].ma) tr[d].num+=tr[lc].num;
    if(tr[d].ma==tr[rc].ma) tr[d].num+=tr[rc].num;
}
void build(int d,int l,int r)
{
    tr[d].l=l,tr[d].r=r;tr[d].maa=tr[d].lz=-1;
    if(l==r)  {tr[d].su=tr[d].ma=a[l];tr[d].num=1;return;}
    int mid=(l+r)>>1;
    build(lc,l,mid);
    build(rc,mid+1,r);
    push(d);
}
void pushh(int d)
{
    if(tr[d].lz==-1) return;
    if(tr[d].lz<tr[lc].ma) tr[lc].su+=1ll*(tr[d].lz-tr[lc].ma)*tr[lc].num,tr[lc].ma=tr[lc].lz=tr[d].lz;
    if(tr[d].lz<tr[rc].ma) tr[rc].su+=1ll*(tr[d].lz-tr[rc].ma)*tr[rc].num,tr[rc].ma=tr[rc].lz=tr[d].lz;
    tr[d].lz=-1;
}
void add(int d,int l,int r,int pos)
{
    if(pos>=tr[d].ma) return;
    if(tr[d].l==l&&tr[d].r==r&&pos>tr[d].maa)
    {
        tr[d].lz=pos;
        tr[d].su+=1ll*(pos-tr[d].ma)*tr[d].num;
        tr[d].ma=pos;return;
    }
    pushh(d);
    int mid=(tr[d].l+tr[d].r)>>1;
    if(mid>=r)  add(lc,l,r,pos);
    else if(l>mid)  add(rc,l,r,pos);
    else add(lc,l,mid,pos),add(rc,mid+1,r,pos);
    push(d);
}
int query(int d,int l,int r)
{
    if(tr[d].l==l&&tr[d].r==r) return tr[d].ma;
    pushh(d);
    int mid=(tr[d].l+tr[d].r)>>1;
    if(mid>=r)  return query(lc,l,r);
    else if(l>mid)  return query(rc,l,r);
    else return max(query(lc,l,mid),query(rc,mid+1,r));
}
ll query1(int d,int l,int r)
{
    if(tr[d].l==l&&tr[d].r==r) return tr[d].su;
    pushh(d);
    int mid=(tr[d].l+tr[d].r)>>1;
    if(mid>=r)  return query1(lc,l,r);
    else if(l>mid)  return query1(rc,l,r);
    else return query1(lc,l,mid)+query1(rc,mid+1,r);
}
int main()
{
    cin.tie(0);
    cout.tie(0);
    cin>>t;
    while(t--)
    {
        n=read(),m=read();
        FOR(i,1,n) a[i]=read();
        build(1,1,n);
        while(m--)
        {
            op=read(),x=read(),y=read();
            if(op==0) z=read(),add(1,x,y,z);
            else if(op==1) printf("%d\n",query(1,x,y));
            else printf("%lld\n",query1(1,x,y));
        }
    }
    return 0;
}