rt

blog链接

hzwer源代码

#include<map>
#include<set>
#include<cmath>
#include<stack>
#include<queue>
#include<cstdio>
#include<vector>
#include<cstring>
#include<cstdlib>
#include<iostream>
#include<algorithm>
#define mod 998244353
#define pi acos(-1)
#define inf 0x7fffffff
#define ll long long
using namespace std;
ll read()
{
    ll x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
    return x*f;
}
int n,blo;
int v[100005],bl[100005],atag[100005];
set<int>st[105];
void add(int a,int b,int c)
{
    for(int i=a;i<=min(bl[a]*blo,b);i++)
    {
        st[bl[a]].erase(v[i]);
        v[i]+=c;
        st[bl[a]].insert(v[i]);
    }
    if(bl[a]!=bl[b])
    {
        for(int i=(bl[b]-1)*blo+1;i<=b;i++)
        {
            st[bl[b]].erase(v[i]);
            v[i]+=c;
            st[bl[b]].insert(v[i]);
        }
    }
    for(int i=bl[a]+1;i<=bl[b]-1;i++)
        atag[i]+=c;
}
int query(int a,int b,int c)
{
    int ans=-1;
    for(int i=a;i<=min(bl[a]*blo,b);i++)
    {
        int val=v[i]+atag[bl[a]];
        if(val<c)ans=max(val,ans);
    }
    if(bl[a]!=bl[b])        
        for(int i=(bl[b]-1)*blo+1;i<=b;i++)        
        {
            int val=v[i]+atag[bl[b]];
            if(val<c)ans=max(val,ans);
        }
    for(int i=bl[a]+1;i<=bl[b]-1;i++)
    {
        int x=c-atag[i];
        set<int>::iterator it=st[i].lower_bound(x);
        if(it==st[i].begin())continue;
        --it;
        ans=max(ans,*it+atag[i]);
    }
    return ans;
}
int main()
{
    n=read();blo=1000;
    for(int i=1;i<=n;i++)v[i]=read();
    for(int i=1;i<=n;i++)
    {
        bl[i]=(i-1)/blo+1;
        st[bl[i]].insert(v[i]);
    }
    for(int i=1;i<=n;i++)
    {
        int f=read(),a=read(),b=read(),c=read();
        if(f==0)add(a,b,c);
        if(f==1)printf("%d\n",query(a,b,c));
    }
    return 0;
}

想知道为什么每一次add的时候排序都需要加上erase(v[i)呢？:(