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poj 3468 线段树成段更新
http://poj.org/problem?id=3468
Time Limit: 5000MS | Memory Limit: 131072K | |
Total Submissions: 58132 | Accepted: 17704 | |
Case Time Limit: 2000MS |
Description
You have N integers, A1, A2, ... , AN. You need to deal with two kinds of operations. One type of operation is to add some given number to each number in a given interval. The other is to ask for the sum of numbers in a given interval.
Input
The first line contains two numbers N and Q. 1 ≤ N,Q ≤ 100000.
The second line contains N numbers, the initial values of A1, A2, ... , AN. -1000000000 ≤ Ai ≤ 1000000000.
Each of the next Q lines represents an operation.
"C a b c" means adding c to each of Aa, Aa+1, ... , Ab. -10000 ≤ c ≤ 10000.
"Q a b" means querying the sum of Aa, Aa+1, ... , Ab.
Output
You need to answer all Q commands in order. One answer in a line.
Sample Input
10 51 2 3 4 5 6 7 8 9 10Q 4 4Q 1 10Q 2 4C 3 6 3Q 2 4
Sample Output
455915
Hint
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Life is so hard! many courage and not care the result!
成段更新不容易啊,看了两三天了,仍像云里雾里,不懂啊!
#include <stdio.h>#include <string.h>#include <stdlib.h>#include <algorithm>#define Maxx 100010int n,m;int str[Maxx];long long ans;struct Node{ int left,right; long long add,sum;}tree[Maxx*4];void build(int l,int r,int rt){ tree[rt].left=l; tree[rt].right=r; tree[rt].add=0; if(l == r) { tree[rt].sum=str[l]; return ; } int mid=(l+r)/2; build(l,mid,2*rt); build(mid+1,r,2*rt+1); tree[rt].sum=tree[rt*2].sum+tree[rt*2+1].sum;}void update(int l,int r,int add,int rt){ if(tree[rt].left>=l && tree[rt].right<=r) { tree[rt].sum+=(tree[rt].right-tree[rt].left+1)*add; tree[rt].add+=add; return ; } if(tree[rt].left>r || tree[rt].right<l) { return ; } if(tree[rt].add) { tree[2*rt].sum += (tree[2*rt].right-tree[2*rt].left+1)*tree[rt].add; tree[2*rt].add += tree[rt].add; tree[2*rt+1].sum += (tree[2*rt+1].right-tree[2*rt+1].left+1)*tree[rt].add; tree[2*rt+1].add += tree[rt].add; tree[rt].add = 0; } update(l,r,add,rt*2); update(l,r,add,rt*2+1); tree[rt].sum =tree[rt*2].sum+tree[rt*2+1].sum;}void query(int l,int r,int rt){ if(tree[rt].left>r || tree[rt].right<l) { return ; } if(tree[rt].left>=l && tree[rt].right<=r) { ans+=tree[rt].sum; return ; } if(tree[rt].add) { tree[2*rt].sum += (tree[2*rt].right-tree[2*rt].left+1)*tree[rt].add; tree[2*rt].add += tree[rt].add; tree[2*rt+1].sum += (tree[2*rt+1].right-tree[2*rt+1].left+1)*tree[rt].add; tree[2*rt+1].add += tree[rt].add; tree[rt].add = 0; } query(l,r,rt*2); query(l,r,rt*2+1); tree[rt].sum=tree[rt*2].sum+tree[rt*2+1].sum;}int main(){ int i,j,k,t,a,b,c; while(scanf("%d%d",&n,&m)!=EOF) { for(i=1;i<=n;i++) { scanf("%d",&str[i]); } build(1,n,1); char st[2]; for(i=1;i<=m;i++) { scanf("%s",st); if(st[0] == ‘Q‘) { scanf("%d%d",&a,&b); ans=0; query(a,b,1); printf("%lld\n",ans); } else { scanf("%d%d%d",&a,&b,&c); update(a,b,c,1); } } } return 0;}