src/segtree/dual_segtree.hpp

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Last update: 2025-12-30 15:03:15+09:00
Include: #include "src/segtree/dual_segtree.hpp"

Depends on

src/template.hpp

Verified with

src/test/aoj_DSL_2_D.cpp

Code

#pragma once
#include "../template.hpp"

//伝搬一切しないver
template<class F,F (*id)(),void (*cmpo)(const F&,F&)> struct dual_segtree {
    dual_segtree():dual_segtree(1){}
    explicit dual_segtree(int n_):n(__bit_ceil(n_)),d(2*n,id()){}
    void apply(int l,int r,F f){
        if(l==r) return;
        for(l+=n,r+=n;l<r;l>>=1,r>>=1){
            if(l&1) cmpo(f,d[l++]);
            if(r&1) cmpo(f,d[--r]);
        }
    }
    F get(int i){
        F r=id();
        for(i+=n;i;i>>=1) cmpo(d[i],r);
        return r;
    }
private:
    int n;
    vector<F> d;
};

#line 2 "src/template.hpp"
#include <bits/stdc++.h>
using namespace std;
#define si(a) (long)a.size()
#define fi first
#define se second
#define all(x) x.begin(),x.end()
#define rep(i,n) for(int i=0;i<(int)(n);++i)
template<typename S,typename F> bool chmin(S&a,F b){return b<a?(a=b,1):0;}
template<typename S,typename F> bool chmax(S&a,F b){return b>a?(a=b,1):0;}
bool _=(ios::sync_with_stdio(0),cin.tie(0),cout<<fixed<<setprecision(16),0);
#line 3 "src/segtree/dual_segtree.hpp"

//伝搬一切しないver
template<class F,F (*id)(),void (*cmpo)(const F&,F&)> struct dual_segtree {
    dual_segtree():dual_segtree(1){}
    explicit dual_segtree(int n_):n(__bit_ceil(n_)),d(2*n,id()){}
    void apply(int l,int r,F f){
        if(l==r) return;
        for(l+=n,r+=n;l<r;l>>=1,r>>=1){
            if(l&1) cmpo(f,d[l++]);
            if(r&1) cmpo(f,d[--r]);
        }
    }
    F get(int i){
        F r=id();
        for(i+=n;i;i>>=1) cmpo(d[i],r);
        return r;
    }
private:
    int n;
    vector<F> d;
};