第五届山东省ACM Devour Magic

Devour Magic

n个单位,每个单位每秒增加1法力,在某些时间取走一些区间的法力值(取走之后该区间所有单位的法力变为0),求取得的所有法力值。

就是在原来的基础上增加了清零的操作,不过这个清零(实际代码中也可以置为任意值)的操作通过flag标志和一个sset变量来保存下要置的数,其他操作和正常pushdown一样,每次在输入时记录上一次更新的时间last,这一次直接t-last就好了。。。

之前的一个超时代码也先粘在这里吧,(标记的可能多搜了!!!),但是提交AC的代码和自己的思路是一模一样的,具体现在也不知道问题出在哪里

超时代码:

///线段树区间更新  
#include<algorithm>  
#include<cstdio>  
#include<cstring>  
#include<cstdlib>  
#include<iostream>  
#include<vector>  
#include<queue>  
#include<stack>  
#include<iomanip>  
#include<string>  
#include<climits>  
#include<cmath>  
#define INF 0x3f3f3f3f  
#define MAX 1100000  
#define LL long long  
using namespace std;  
LL n,m;  
LL coun=0;  
int xx;  
  
struct Tree  
{  
  LL l,r;  
  LL sum,add;  
};  
Tree tree[MAX*8];  
  
void pushup(LL x)  ///更新父节点  
{  
  tree[x].sum=tree[ x<<1 ].sum+tree[ (x<<1)+1 ].sum;  
}  
  
void pushdown(LL x)  ///用于更新add数组  
{  
  if(x>xx){  
    tree[x].sum = 0;  
    return ;  
  }  
  LL tmp = x<<1 ;  
  if(tree[x].add == -INF){  
   //  cout<<x<<"----------------------"<<endl;  
      tree[tmp].add = -INF ;  ///由子节点通过增加  
      tree[tmp+1].add = -INF;  
      tree[tmp].sum = 0;  
      tree[tmp+1].sum = 0;  
      tree[x].add=0;  
      tree[x].sum=0;  
      return ;  
  }  
  if( tmp > xx ) return ;  
  if(tree[tmp].add == -INF )   pushdown(tmp);  
  if(tree[tmp+1].add == -INF)  pushdown(tmp+1);  
  
  
  tree[tmp].add +=  tree[x].add;  ///由子节点通过增加  
  tree[tmp].sum += tree[x].add*(tree[tmp].r-tree[tmp].l+1);  
  
  tree[tmp+1].add += tree[x].add;  
  tree[tmp+1].sum += tree[x].add*(tree[tmp+1].r-tree[tmp+1].l+1);  
  if(tmp>xx) cout<<tmp<<"  "<<tree[tmp].add<<"  "<<tree[tmp].add<<"  "<<tree[tmp].l<<"  "<<tree[tmp].r<<endl;  
  tree[x].add=0;  
}  
  
void build(int l,int r,int x)  
{  
  tree[x].l=l , tree[x].r=r , tree[x].add=0;  
  if(l==r)  
  {  
    tree[x].sum = 0;  ///子节点初始化  
    tree[x].add = 0;  
    return ;  
  }  
  int tmp=x<<1;  
  int mid=(l+r)>>1;  
  build(l,mid,tmp);  
  build(mid+1,r,tmp+1);  
  pushup(x);  ///建立时需根据子节点更细父亲节点  
}  
  
  
void update(LL l,LL r,LL c,LL x)  ///分别表示区间的左 , 右 , 增加的值  ,当前父亲节点  
{  
  if(r<tree[x].l||l>tree[x].r||x>xx)   return ;  
  if(l<=tree[x].l&&r>=tree[x].r)  ///该区间为需要更新区间的子区间  
  {  
   // cout<<"************
";  
    if(c==-INF){  
        tree[x].add = -INF;  
        tree[x].sum = 0;  
        return ;  
    }  
    if(x>xx)  return ;  
    if(tree[x].add == -INF ) pushdown(x);  
  
  
    tree[x].add += c ;  
    tree[x].sum += c*(tree[x].r-tree[x].l+1); ///区间长度*要增加的数值  
    return ;  
  }  
  
  ///如果比当前的范围还小,就通过该节点向下更新下面的节点  
  if(tree[x].add  )  pushdown(x);  ///更新从上向下更新add  
  
  LL tmp=x<<1;  
  if(tmp>xx){  
    pushup(x);  
    return ;  
  }  
  update(l,r,c,tmp);  
  update(l,r,c,tmp+1);  
}  
  
LL query(LL l,LL r,LL x)  
{  
  ///if(r<tree[x].l||l>tree[x].r)     return -INF;//要更新的区间不在该区间上(输入有误)  
  if(l<=tree[x].l&&r>=tree[x].r)    ///要计算的区间包括了该区间  
  {  
    return tree[x].sum;  
  }  
  if( tree[x].add&&tree[x].add!=-INF )   pushdown(x);  ///如果add不为零,对查询可能用到的add更新  
  LL tmp=x<<1;  
  if(tmp>xx) return 0;  
  LL mid=(tree[x].l+tree[x].r)>>1;  
  
  if(r<=mid)   return query(l,r,tmp);  
  else if(l>mid)  return query(l,r,tmp+1);  
  else  return query(l,mid,tmp)+query(mid+1,r,tmp+1);  
}  
  
int main()  
{  
  int xxx;  
  scanf("%d",&xxx);  
  while(xxx--)  
  {  
    scanf("%I64d%I64d",&n,&m);  
    xx=4*n;  
    coun=0;  
    build(1,n,1);  
    LL last=0;  
    while(m--)  
    {  
        LL l,r,time;  
        scanf("%I64d%I64d%I64d",&time,&l,&r);  
        update(1,n,time-last,1);  
/* 
       cout<<"加"<<time-last<<endl; 
        for(int i=1;i<=60;i++) 
            cout<<i<<":"<<tree[i].add<<' '<<tree[i].sum<<"    "; 
        cout<<endl;*/  
        last = time ;  
        coun+=query(l,r,1);  
        update(l,r,-INF,1);  
/* 
         for(int i=1;i<=60;i++) 
          cout<<i<<":"<<tree[i].add<<' '<<tree[i].sum<<"      "; 
          cout<<endl;*/  
    }  
    printf("%I64d
",coun);  
  }  
  return 0;  
}  
/************************************** 
    Problem id  : SDUT OJ 2880  
    User name   : 张士卫  
    Result      : Time Limit Exceeded  
    Take Memory : 0K  
    Take Time   : 2010MS  
    Submit Time : 2016-04-02 09:36:52   
**************************************/  


AC代码:

#include<iostream>  
#include<stdio.h>  
#include<string.h>  
using namespace std;  
  
#define L(root) ((root)<<1)  
#define R(root) (((root)<<1)|1)  
  
const int MAXN=1e5+10;//  
int numbers[MAXN];//初始值  
  
struct node{  
    int left,right;///  
    long long sum;  
    int add;///区间增加值  
    int sset;    ///区间里的数设为v  
    bool flag;///标记是否设置为v  
    int mid(){  
        return ((right+left)>>1);  
    }  
}tree[MAXN*4];//4倍空间  
  
void pushUp(int root){  
    tree[root].sum=tree[L(root)].sum+tree[R(root)].sum;  
}  
  
void pushDown(int root){  
    int L=L(root),R=R(root);  
    if(tree[root].flag){  
        tree[L].add=tree[R].add=0;  
        tree[L].sset=tree[R].sset=tree[root].sset;  
        tree[L].flag=tree[R].flag=true;  
        tree[L].sum=tree[root].sset*(tree[L].right-tree[L].left+1);  
        tree[R].sum=tree[root].sset*(tree[R].right-tree[R].left+1);  
        tree[root].flag=false;  
    }  
    if(tree[root].add){  ///正常pushdown  
        tree[L].add+=tree[root].add;  
        tree[R].add+=tree[root].add;  
        tree[L].sum+=tree[root].add*(tree[L].right-tree[L].left+1);  
        tree[R].sum+=tree[root].add*(tree[R].right-tree[R].left+1);  
        tree[root].add=0;  
    }  
}  
  
void build(int root,int left,int right){  
    tree[root].left=left;  
    tree[root].right=right;  
    tree[root].add=0;  
    tree[root].flag=false;  
    if(left==right){  
        tree[root].sum=numbers[left];  
        return;  
    }  
    int mid=tree[root].mid();  
    build(L(root),left,mid);  
    build(R(root),mid+1,right);  
    pushUp(root);  
}  
  
long long query(int root,int left,int right){  
    if(tree[root].left==left&&tree[root].right==right)  return tree[root].sum;  
  
    pushDown(root);  
    int mid=tree[root].mid();  
  
    if(right<=mid)  return query(L(root),left,right);  
    else if(left>mid)  return query(R(root),left,right);  
    else  return query(L(root),left,mid)+query(R(root),mid+1,right);  
}  
  
void update(int root,int left,int right,int add){  
    if(tree[root].left==left&&tree[root].right==right){  
        tree[root].add+=add;  
        tree[root].sum+=add*(right-left+1);  
        return;  
    }  
  
    pushDown(root);  
    int mid=tree[root].mid(),L=L(root),R = R(root);  
    if(right<=mid)     update(L,left,right,add);  
    else if(left>mid)  update(R,left,right,add);  
    else{  
        update(L,left,mid,add);  
        update(R,mid+1,right,add);  
    }  
    pushUp(root);  
}  
  
void setf(int root,int left,int right,int sset){  
    if(tree[root].left==left&&tree[root].right==right){  
        tree[root].add=0;  
        tree[root].sum=sset*(right-left+1);  
        tree[root].sset=sset;  
        tree[root].flag=true;  
        return;  
    }  
    pushDown(root);  
    int mid=tree[root].mid(),L=L(root),R = R(root);  
    if(right<=mid)     setf(L,left,right,sset);  
    else if(left>mid)  setf(R,left,right,sset);  
    else{  
        setf(L,left,mid,sset);  
        setf(R,mid+1,right,sset);  
    }  
    pushUp(root);  
}  
  
  
int main(){  
  
    memset(numbers,0,sizeof(numbers));  
  
    int T;  
    int n,m;  
    int t,l,r;  
    int i;  
    int lastTime;  
    long long sum;  
  
    scanf("%d",&T);  
  
    while(T--){  
  
        scanf("%d%d",&n,&m);  
        build(1,1,n);  
  
        lastTime=0;  
        sum=0;  
        for(i=0;i<m;++i){  
            scanf("%d%d%d",&t,&l,&r);  
  
            update(1,1,n,t-lastTime);  
            sum+=query(1,l,r);  
            setf(1,l,r,0);//l到r区间设为0  
  
            lastTime=t;  
        }  
  
        printf("%lld
",sum);  
  
    }  
    return 0;  
}  



原文地址:https://www.cnblogs.com/zswbky/p/6717959.html