poj 3468 A Simple Problem with Integers（线段树区间更新）

Description

You have N integers, A₁, A₂, ... , A_N. 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, ... , A_N. -1000000000 ≤ A_i ≤ 1000000000.
Each of the next Q lines represents an operation.
"C a b c" means adding c to each of A_a, A_a+1, ... , A_b. -10000 ≤ c ≤ 10000.
"Q a b" means querying the sum of A_a, A_a+1, ... , A_b.

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

 #include <iostream>
 #include <cstdio>
 using namespace std;
 #define LL long long
 #define lson rt<<1,first,mid
 #define rson rt<<1 | 1,mid+1,end
 const int maxn=;
 LL tree[maxn<<];
 LL add[maxn<<];
 void push_up(int rt)
 {
     tree[rt]=tree[rt<<]+tree[rt<< | ];
 }
 void push_down(int rt,int m) //更新子节点的数值
 {
     if(add[rt])
     {
         add[rt<<]+=add[rt];
         add[rt<<|]+=add[rt];
         tree[rt<<]+=add[rt]*(m-(m>>));
         tree[rt<<|]+=add[rt]*(m>>);
         add[rt]=; //更新后需要还原
     }
 }
 void build(int rt,int first,int end)
 {
     add[rt]=;
     if(first==end)
     {
         scanf("%lld",&tree[rt]);
         //cin>>tree[rt];
         return ;
     }
     int mid=(first+end)>>;
     build(lson);
     build(rson);
     push_up(rt);
     return ;
 }
 LL query(int rt,int first,int end,int a,int b) //求区间和
 {
        if(first>=a&&end<=b)
         return tree[rt];
     push_down(rt,end-first+);
     LL sum=;
     int mid=(first+end)>>;
     if(a<=mid)
         sum+=query(lson,a,b);
     if(b>mid)
         sum+=query(rson,a,b);
     return sum;
 }
 void update(int rt,int first,int end,int a,int b,int c)
 {
     if(first>=a&&end<=b)
     {
         add[rt]+=c;
         tree[rt]+=(LL)c*(end-first+);
         return ;
     }
     push_down(rt,end-first+);
     int mid=(first+end)>>;
     if(a<=mid)
         update(lson,a,b,c);
     if(b>mid)
         update(rson,a,b,c);
     push_up(rt);
     return ;
 }
 int main()
 {
     int n,q;
     char ch[];
     int a,b,c;
     scanf("%d%d",&n,&q);
     //cin>>n>>q;
     build(,,n);
     while(q--)
     {
         scanf("%s",ch);
         //cin>>ch;
         if(ch[]=='Q')
         {
             scanf("%d%d",&a,&b);
             printf("%lld\n",query(,,n,a,b));
             //cin>>a>>b;
             //cout<<query(1,1,n,a,b)<<endl;
         }
         if(ch[]=='C')
         {
             scanf("%d%d%d",&a,&b,&c);
             //cin>>a>>b>>c;
             update(,,n,a,b,c);
         }
     }
     return ;
 }