• hdu4267 A Simple Problem with Integers


    A Simple Problem with Integers

    Time Limit: 5000/1500 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
    Total Submission(s): 2571 Accepted Submission(s): 837

    Problem Description
    Let A1, A2, ... , AN be N elements. You need to deal with two kinds of operations. One type of operation is to add a given number to a few numbers in a given interval. The other is to query the value of some element.
     
    Input
    There are a lot of test cases.
    The first line contains an integer N. (1 <= N <= 50000)
    The second line contains N numbers which are the initial values of A1, A2, ... , AN. (-10,000,000 <= the initial value of Ai <= 10,000,000)
    The third line contains an integer Q. (1 <= Q <= 50000)
    Each of the following Q lines represents an operation.
    "1 a b k c" means adding c to each of Ai which satisfies a <= i <= b and (i - a) % k == 0. (1 <= a <= b <= N, 1 <= k <= 10, -1,000 <= c <= 1,000)
    "2 a" means querying the value of Aa. (1 <= a <= N)
     
    Output
    For each test case, output several lines to answer all query operations.
     
    Sample Input
    4 1 1 1 1 14 2 1 2 2 2 3 2 4 1 2 3 1 2 2 1 2 2 2 3 2 4 1 1 4 2 1 2 1 2 2 2 3 2 4
     
    Sample Output
    1 1 1 1 1 3 3 1 2 3 4 1
    这题好卡内存,发现用结构比直接用数组要省很多啊,结果搞的我卡了不知道多少次啊!分析一下题,一看,就知道是要用线段树,但是和别的不一样,就是,它是单点更新,
    为什么是单点更新呢?因为在一个区间上,并不是没一个都要更新!但这一点,对于线段树来说,就是非常不利的了,因为,线段树就是要成段更新,如果是,一个点一个点,
    那么线段树便失去了作用,那么还有什么意义呢?所以,我们要用一个数组,先保存所有要更新的信息,也就是(i-a)%k==0转化成(i%k)==l%k;因为l%k是很快可以算出来的,我在在要更新区间上,把这个相应的数组加累加起来,也就是把所有的(l%k)加起来,到了最后查询的时候只把,(i%k),的加起来,这样,不但满足了题意,也用了延时标记,把点连成了线,最后要查询的时候,再把所有的和加起来并更新,就可以了!很好线段树了!
    #include <string.h>
    #include <iostream>
    #include <stdio.h>
    using namespace std;
    #define MAXN 50005
    #define lnum num<<1
    #define rnum num<<1|1
    
    struct node
    {
        int color,prime,listadd[55];
    }tree[4*MAXN];
    #define inf 0
    int modleft[11][11];
    void build(int num ,int l,int r)
    {
        memset(tree[num].listadd,0,sizeof(tree[num].listadd));
        tree[num].color=0;
        int mid=(l+r)>>1;
        if(l>=r)
        {
            scanf("%d",&tree[num].prime);
            return ;
        }
        build(lnum,l,mid);
        build(rnum,mid+1,r);
    }
    void pushdown(int num)
    {
        int i;
         if(tree[num].color!=inf)
        {
    
                tree[lnum].color=tree[num].color;
                tree[rnum].color=tree[num].color;
                tree[num].color=inf;//还原标记
    
                for(i=0;i<55;i++)
                {
    
                    tree[lnum].listadd[i]+=tree[num].listadd[i];
                    tree[rnum].listadd[i]+=tree[num].listadd[i];
                    tree[num].listadd[i]=0;
    
                }
        }
    }
    void update(int s,int e,int a,int b,int num,int amk,int k,int c )
    {
        int i;
    
    
        if(a<=s&&b>=e)
        {
            tree[num].color=k;//需要更新
            tree[num].listadd[modleft[k][amk]]+=c;
            return ;
        }
        pushdown(num);
      int mid=(s+e)>>1;
      if(mid>=a)
      update(s,mid,a,b,lnum,amk,k,c);
      if(mid<b)
      update(mid+1,e,a,b,rnum,amk,k,c);
    }
    int query(int s,int e,int num,int x)//充分利用这个延时标记
    {
        int i;
    
    
        if(s>=e)
        {
            int temp=tree[num].prime;
            for(i=1;i<=10;i++)
            {
                temp+=tree[num].listadd[modleft[i][x%i]];
                tree[num].listadd[modleft[i][x%i]]=0;
            }
            tree[num].prime=temp;//更新为新的值
            return temp;
        }
        pushdown(num);
        int mid=(s+e)>>1;
        if(x>mid)
            return query(mid+1,e,rnum,x);
        else
        {
            return query(s,mid,lnum,x);
        }
    }
    int main()
    {
        int asknum,num12,x,a,b,n,k,c;
        int i,j,cnt=0;
        for(i=1;i<=10;i++)
            for(j=0;j<i;j++)
            {
                modleft[i][j]=cnt++;//省了一半的空间
            }
        while(scanf("%d",&n)!=EOF)
        {
            build(1,1,n);
    
            scanf("%d",&asknum);
            while(asknum--)
            {
    
               scanf("%d",&num12);
               if(num12==1)
               {
                  scanf("%d%d%d%d",&a,&b,&k,&c);
    
                  update(1,n,a,b,1,a%k,k,c);
               }
               else{
                  scanf("%d",&x);
                  printf("%d
    ",query(1,n,1,x));
               }
    
            }
        }
        return 0;
    }
    


  • 相关阅读:
    Django进阶Model篇006
    nginx 实现反向代理、负载均衡、高可用
    【springcloud】Zuul高级配置(zuul--3)
    【springcloud】Zuul高级配置(zuul--2)
    【springcloud】API Gateway 的路由和过滤(Zuul--1)
    【springcloud】服务熔断与降级(Hystrix)
    【springcloud】hystrix面试题
    时间复杂度On和空间复杂度O1是什么意思?
    2019年 Java 面试题解析
    【springcloud】模拟RPC调用(Feign)
  • 原文地址:https://www.cnblogs.com/javawebsoa/p/3220081.html
Copyright © 2020-2023  润新知