• E. Physical Education Lessons 动态开辟线段树区间更新


    E. Physical Education Lessons
    time limit per test
    1 second
    memory limit per test
    256 megabytes
    input
    standard input
    output
    standard output

    This year Alex has finished school, and now he is a first-year student of Berland State University. For him it was a total surprise that even though he studies programming, he still has to attend physical education lessons. The end of the term is very soon, but, unfortunately, Alex still hasn't attended a single lesson!

    Since Alex doesn't want to get expelled, he wants to know the number of working days left until the end of the term, so he can attend physical education lessons during these days. But in BSU calculating the number of working days is a complicated matter:

    There are n days left before the end of the term (numbered from 1 to n), and initially all of them are working days. Then the university staff sequentially publishes q orders, one after another. Each order is characterised by three numbers l, r and k:

    • If k = 1, then all days from l to r (inclusive) become non-working days. If some of these days are made working days by some previous order, then these days still become non-working days;
    • If k = 2, then all days from l to r (inclusive) become working days. If some of these days are made non-working days by some previous order, then these days still become working days.

    Help Alex to determine the number of working days left after each order!

    Input

    The first line contains one integer n, and the second line — one integer q (1 ≤ n ≤ 109, 1 ≤ q ≤ 3·105) — the number of days left before the end of the term, and the number of orders, respectively.

    Then q lines follow, i-th line containing three integers li, ri and ki representing i-th order (1 ≤ li ≤ ri ≤ n, 1 ≤ ki ≤ 2).

    Output

    Print q integers. i-th of them must be equal to the number of working days left until the end of the term after the first i orders are published.

    Example
    Input
    4
    6
    1 2 1
    3 4 1
    2 3 2
    1 3 2
    2 4 1
    1 4 2
    Output
    2
    0
    2
    3
    1
    4
    #include<cstdio>
    #include<cstring>
    #include<algorithm>
    using namespace std;
    const int N=15000000;
    int rt=1,LL[N],RR[N],V[N],tot=1,lazy[N];
    void pdw(int x,int val){
        if(lazy[x]!=-1) {
            if(!LL[x]) LL[x]=++tot;if(!RR[x]) RR[x]=++tot;
            if(lazy[x]) V[LL[x]]=(val+1)/2,V[RR[x]]=val/2;
            else V[LL[x]]=V[RR[x]]=0;
            lazy[LL[x]]=lazy[RR[x]]=lazy[x];
            lazy[x]=-1;
        }
    }
    void update(int &x,int l,int r,int L,int R,bool f){
        if(!x) x=++tot;
        if(L>=l&&R<=r) {
            if(f) V[x]=R-L+1;else V[x]=0;
            lazy[x]=f;
            return;
        }
        pdw(x,R-L+1);
        int mid=(L+R)>>1;
        if(l<=mid) update(LL[x],l,r,L,mid,f);
        if(r>mid) update(RR[x],l,r,mid+1,R,f);
        V[x]=V[LL[x]]+V[RR[x]];
    }
    int main(){
        int n,m,x,y,z;
        scanf("%d%d",&n,&m);
        memset(lazy,-1,sizeof(lazy));
        for(int i=1;i<=m;++i) {
            scanf("%d%d%d",&x,&y,&z);
            update(rt,x,y,1,n,z==1);
            printf("%d
    ",n-V[1]);
        }
    }

     set做法

    离散化线段树做法

  • 相关阅读:
    常用数字处理小技巧
    C# 绘制统计图(柱状图, 折线图, 扇形图) zhuan
    谈谈防 SQL 注入式攻击策略
    ASP.NET2.0小技巧--内部控件权限的实现
    宝刀不老: Cookie
    IP地址与子网掩码总结
    ASP.NET 2.0下实现匿名用户向注册用户的迁移(上) zhuan
    [翻译].net 2.0(c#)下简单的FTP应用程序 zhuan
    ASP.NET2.0自动搜索文件组成导航系统
    正则表达式实现资料验证的技术总结
  • 原文地址:https://www.cnblogs.com/mfys/p/8404967.html
Copyright © 2020-2023  润新知