HDU 4288 Coder
Coder
Time Limit: 20000/10000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1260 Accepted Submission(s): 551
Problem Description
In mathematics and computer science, an algorithm describes a set of procedures or instructions that define a procedure. The term has become increasing popular since the advent of cheap and reliable computers. Many companies now employ a single coder to write an algorithm that will replace many other employees. An added benefit to the employer is that the coder will also become redundant once their work is done. 1
You are now the signle coder, and have been assigned a new task writing code, since your boss would like to replace many other employees (and you when you become redundant once your task is complete).
Your code should be able to complete a task to replace these employees who do nothing all day but eating: make the digest sum.
By saying “digest sum” we study some properties of data. For the sake of simplicity, our data is a set of integers. Your code should give response to following operations:
1. add x – add the element x to the set;
2. del x – remove the element x from the set;
3. sum – find the digest sum of the set. The digest sum should be understood by
![](http://acm.hdu.edu.cn/data/images/C415-1001-1.jpg)
where the set S is written as {a1, a2, ... , ak} satisfying a1 < a2 < a3 < ... < ak
Can you complete this task (and be then fired)?
------------------------------------------------------------------------------
1 See http://uncyclopedia.wikia.com/wiki/Algorithm
You are now the signle coder, and have been assigned a new task writing code, since your boss would like to replace many other employees (and you when you become redundant once your task is complete).
Your code should be able to complete a task to replace these employees who do nothing all day but eating: make the digest sum.
By saying “digest sum” we study some properties of data. For the sake of simplicity, our data is a set of integers. Your code should give response to following operations:
1. add x – add the element x to the set;
2. del x – remove the element x from the set;
3. sum – find the digest sum of the set. The digest sum should be understood by
![](http://acm.hdu.edu.cn/data/images/C415-1001-1.jpg)
where the set S is written as {a1, a2, ... , ak} satisfying a1 < a2 < a3 < ... < ak
Can you complete this task (and be then fired)?
------------------------------------------------------------------------------
1 See http://uncyclopedia.wikia.com/wiki/Algorithm
Input
There’re several test cases.
In each test case, the first line contains one integer N ( 1 <= N <= 105 ), the number of operations to process.
Then following is n lines, each one containing one of three operations: “add x” or “del x” or “sum”.
You may assume that 1 <= x <= 109.
Please see the sample for detailed format.
For any “add x” it is guaranteed that x is not currently in the set just before this operation.
For any “del x” it is guaranteed that x must currently be in the set just before this operation.
Please process until EOF (End Of File).
In each test case, the first line contains one integer N ( 1 <= N <= 105 ), the number of operations to process.
Then following is n lines, each one containing one of three operations: “add x” or “del x” or “sum”.
You may assume that 1 <= x <= 109.
Please see the sample for detailed format.
For any “add x” it is guaranteed that x is not currently in the set just before this operation.
For any “del x” it is guaranteed that x must currently be in the set just before this operation.
Please process until EOF (End Of File).
Output
For each operation “sum” please print one line containing exactly one integer denoting the digest sum of the current set. Print 0 if the set is empty.
Sample Input
9 add 1 add 2 add 3 add 4 add 5 sum add 6 del 3 sum 6 add 1 add 3 add 5 add 7 add 9 sum
Sample Output
3 4 5
Hint
C++ maybe run faster than G++ in this problem.Source
Recommend
liuyiding
// 想起刘老师说的线段树节点的信息一定要明确实用,而我老师忘记,每次回忘记节点各变量的意义、、、
// num 代表的是该子树的元素总个数
// sum[5] 代表该区间的 mod 5 =i 的和
#include <iostream> #include <algorithm> #include <cstdio> #include <cstring> #define lson l,m,k<<1 #define rson m+1,r,k<<1|1 #define N 500002 using namespace std; char op[N][10]; int p[N]; int rc[N]; struct node { int num; __int64 sum[6]; }; node st[N<<2]; int nk; int bf(int &x) { int l=1,r=nk,m; while(l<=r) { m=(l+r)>>1; if(rc[m]<x) l=m+1; else if(rc[m]>x) r=m-1; else return m; } } void build(int l,int r,int k) { st[k].num=0; memset(st[k].sum,0,sizeof(st[k].sum)); if(l==r) return ; int m=(l+r)>>1; build(lson); build(rson); } void up(int &k) { int i; for(i=1;i<=5;i++) if(!((i+st[k<<1].num)%5)) break; i=i%5; for(int j=0;j<5;i=(i+1)%5,j++) st[k].sum[j]=st[k<<1].sum[j]+st[k<<1|1].sum[i]; } int flag; void update(int &id,int l,int r,int k) { st[k].num+=flag; if(l==r) { st[k].sum[1]=flag>0?rc[id]:0; return ; } int m=(l+r)>>1; if(id<=m) update(id,lson); else update(id,rson); up(k); } int main() { int n; int i,j; while(scanf("%d",&n)!=EOF) { for(j=1,i=0;i<n;i++) { scanf("%s",op[i]); if(op[i][0]!='s') { scanf("%d",&p[i]); rc[j++]=p[i]; } } sort(rc+1,rc+j); for(nk=1,i=2;i<j;i++) if(rc[i]!=rc[nk]) rc[++nk]=rc[i]; build(1,nk,1); for(i=0;i<n;i++) { if(op[i][0]=='a') { j=bf(p[i]); flag=1; update(j,1,nk,1); } else if(op[i][0]=='d') { j=bf(p[i]); flag=-1; update(j,1,nk,1); } else printf("%I64d\n",st[1].sum[3]); } } return 0; }