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POJ 3468 线段树+lazy标记
lazy标记
Time Limit:5000MS Memory Limit:131072KB 64bit IO Format:%I64d & %I64u
Submit Status
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 abc" means adding c to each of Aa, Aa+1, ... , Ab. -10000 ≤ c ≤ 10000.
"Q ab" 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 5
1 2 3 4 5 6 7 8 9 10
Q 4 4
Q 1 10
Q 2 4
C 3 6 3
Q 2 4
Sample Output
4
55
9
15
Hint
The sums may exceed the range of 32-bit integers.
<span style="color:#6633ff;">/******************************************************** author : Grant Yuan time : 2014.7.28 algorithm : 线段树+lazy标记 source : POJ 3468 *********************************************************/ #include <iostream> #include<cstdio> #include<cstdlib> #include<cstring> #include<algorithm> #define MAX 100003 #define LL long long using namespace std; struct node{ LL l; LL r; LL sum; LL lazy; }; node tree[3*MAX]; int n,m; LL input[MAX],ans; void build(LL left,LL right,LL root) { tree[root].lazy=0; tree[root].l=left; tree[root].r=right; if(left==right){ tree[root].sum=input[left]; return; } int mid=(left+right)>>1; build(left,mid,root*2); build(mid+1,right,root*2+1); tree[root].sum=tree[root*2].sum+tree[root*2+1].sum; } void upchild(LL root) { if(tree[root].lazy){ tree[root<<1].sum+=(tree[root<<1].r-tree[root<<1].l+1)*tree[root].lazy; tree[(root<<1)|1].sum+=(tree[(root<<1)|1].r-tree[(root<<1)|1].l+1)*tree[root].lazy; tree[root<<1].lazy+=tree[root].lazy; tree[root<<1|1].lazy+=tree[root].lazy; tree[root].lazy=0; } } void update(LL left,LL right,LL root,LL p) { if(left<=tree[root].l&&right>=tree[root].r) { tree[root].sum+=(LL)(tree[root].r-tree[root].l+1)*p; tree[root].lazy+=(LL)p; return; } upchild(root); int mid=(tree[root].l+tree[root].r)>>1; if(mid<right) update(left,right,root*2+1,p); if(mid>=left) update(left,right,root*2,p); tree[root].sum=tree[root<<1].sum+tree[(root<<1)|1].sum; } void query(LL left,LL right,LL root) { if(left<=tree[root].l&&right>=tree[root].r) { ans+=(LL)tree[root].sum; return; } upchild(root); int mid=(tree[root].l+tree[root].r)>>1; if(mid>=left) query(left,right,root<<1); if(mid<right) query(left,right,root*2+1); } int main() { char s;LL a,b,q; while(~scanf("%d%d",&n,&m)){ for(int i=1;i<=n;i++) scanf("%lld",&input[i]); build(1,n,1); for(int i=0;i<m;i++) { getchar(); scanf("%c",&s); if(s=='Q'){ ans=0; scanf("%lld%lld",&a,&b); query(a,b,1); printf("%lld\n",ans); } else if(s=='C'){ scanf("%lld%lld%lld",&a,&b,&q); update(a,b,1,q); } } } return 0; } </span>