A Simple Problem with Integers (Fenwick tree section changes, range query)

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

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <algorithm>
 5 using namespace std;
 6 
 7 typedef long long ll;
 8 int t,n,jishu,m;
 9 const int N=100005;
10 ll cnt1[N],arr[N],cnt2[N];
11 int lowbits(int x) { return x&-x; }
12 void add(int x,int value){
13     ll temp=x;
14     while(x<=N){
15         cnt1[x]+=value;
16         cnt2[x]+=value*(temp-1);
17         x+=lowbits(x);
18     }
19 }
20 ll query(int x){
21     ll sum=0;
22     int temp=x;
23     while(x>0){
24         sum+=temp*cnt1[x]-cnt2[x];
25         x-=lowbits(x);
26     }
27     return sum;
28 }
29 
30 int main(){
31 
32     scanf("%d%d",&n,&m);
33     for(int i=1,d;i<=n;i++) scanf("%lld",&arr[i]),add(i,arr[i]-arr[i-1]);
34     char ss[10];
35     for(int i=1;i<=m;i++){
36         int d1,d2,d3;
37         scanf("%s",ss);
38         if(ss[0]=='Q'){
39             scanf("%d%d",&d1,&d2);
40             printf("%lld\n",query(d2)-query(d1-1));
41         }
42         else{
43             scanf("%d%d%d",&d1,&d2,&d3);
44             add(d1,d3),add(d2+1,-d3);
45         }
46     }
47     return 0;
48 }

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