洛谷P2357_分块

预处理每个点所属块序号减少常数

#include <bits/stdc++.h>
/*
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/hash_policy.hpp>
*/
using namespace std;

const double eps = 1e-10;
const double pi = 3.1415926535897932384626433832795;
const double eln = 2.718281828459045235360287471352;

#define f(i, a, b) for (int i = a; i <= b; i++)
#define scan(x) scanf("%d", &x)
#define mp make_pair
#define pb push_back
#define lowbit(x) (x&(-x))

#define fi first
#define se second
#define SZ(x) int((x).size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define summ(a) (accumulate(all(a), 0ll))

typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;

using ll=long long;

ll n,m,kk,a[(int)2e5+9],fk[(int)2e5+9],tag[(int)2e5+9],bl[(int)2e5+9]; 


void update(int l,int r,int x){
    if(bl[l]==bl[r]){
        for(int i=l;i<=r;++i)a[i]+=x,fk[bl[i]]+=x;
        return ;
    }
    int st=bl[l]+1,en=bl[r]-1;
    for(int i=st;i<=en;++i)tag[i]+=x;
    for(int i=l;i<st*kk;++i)a[i]+=x,fk[bl[i]]+=x;
    for(int i=en*kk+kk;i<=r;++i)a[i]+=x,fk[bl[i]]+=x;
}

ll query(int l,int r){
    ll res=0;
    if(bl[l]==bl[r]){
        for(int i=l;i<=r;++i)res+=a[i];
        res+=(r-l+1ll)*tag[l/kk];
        return res;
    }
    int st=bl[l]+1,en=bl[r]-1;
    for(int i=st;i<=en;++i)res+=kk*tag[i]+fk[i];
    for(int i=l;i<st*kk;++i)res+=a[i]+tag[bl[i]];
    for(int i=en*kk+kk;i<=r;++i)res+=a[i]+tag[bl[i]];
    return res;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m;
    kk=sqrt(n)+0.5;
    f(i,1,n)cin>>a[i],fk[i/kk]+=a[i],bl[i]=i/kk;
    for(int i=1,opt,l,r,k;i<=m;++i){
        cin>>opt;
        if(opt==1){
            cin>>l>>r>>k;
            update(l,r,k);
        }else if(opt==2){
            cin>>k;
            update(1,1,k);
        }else if(opt==3){
            cin>>k;
            update(1,1,-k);
        }else if(opt==4){
            cin>>l>>r;
            cout<<query(l,r)<<"\n";
        }else cout<<query(1,1)<<"\n";
    }
    return 0;
}