洛谷P3870_分块

#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,fk[(int)1e5+9],tag[(int)1e5+9],kc,bl[(int)1e5+9],a[(int)1e5+9];
 
void change(int l,int r){
    if(bl[l]==bl[r]){
        for(int i=l;i<=r;++i)a[i]^=1,fk[bl[l]]+=a[i]==1?1:-1;
        return ;
    }
    int st=bl[l]+1,en=bl[r]-1;
    for(int i=st;i<=en;++i)tag[i]^=1;
    for(int i=l;i<st*kc;++i)a[i]^=1,fk[bl[l]]+=a[i]==1?1:-1;
    for(int i=bl[r]*kc;i<=r;++i)a[i]^=1,fk[bl[r]]+=a[i]==1?1:-1;
}

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

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m;
    kc=sqrt(n);
    for(int i=1;i<=n;++i)bl[i]=i/kc;

    for(int i=1,opt,l,r;i<=m;++i){
        cin>>opt>>l>>r;
        if(!opt)change(l,r);
        else cout<<query(l,r)<<"\n";
    }
    return 0;
}