POJ 3468 A Simple Problem with Integers

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

Hint

The sums may exceed the range of 32-bit integers.

线段树功能：update:成段增减 query:区间求和

#include<stdio.h>
#include<string.h>
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define LL long long
const int maxn=111111;
LL add[maxn<<2];
LL sum[maxn<<2];
void pushup(int rt)
{
    sum[rt]=sum[rt<<1]+sum[rt<<1|1];
}
void pushdown(int rt,int m)
{
    if(add[rt])
    {
        add[rt<<1]+=add[rt];
        add[rt<<1|1]+=add[rt];
        sum[rt<<1]+=add[rt]*(m-(m>>1));
        sum[rt<<1|1]+=add[rt]*(m>>1);
        add[rt]=0;
    }
}
void build(int l,int r,int rt)
{
    add[rt]=0;
    if(l==r)
    {
        scanf("%lld",&sum[rt]);
        return;
    }
    int m=(l+r)>>1;
    build(lson);
    build(rson);
    pushup(rt);
}
void update(int L,int R,int c,int l,int r,int rt)
{

    if(L<=l&&r<=R)
    {
        add[rt]+=c;
        sum[rt]+=(LL)c*(r-l+1);
        return;
    }
    pushdown(rt,r-l+1);
    int m=(l+r)>>1;
    if(L<=m)update(L,R,c,lson);
    if(m<R) update(L,R,c,rson);
    pushup(rt);
}
LL query(int L,int R,int l,int r,int rt)
{
    if(L<=l&&r<=R)
        return sum[rt];
    pushdown(rt,r-l+1);
    int m=(l+r)>>1;
    LL ret=0;
    if(L<=m) ret+=query(L,R,lson);
    if(m<R)  ret+=query(L,R,rson);
    return ret;
}
int main()
{
    int n,t,a,b,c;
    char op[2];
    scanf("%d%d",&n,&t);
    build(1,n,1);
    while(t--)
    {
        scanf("%s",op);
        if(op[0]=='Q')
        {
            scanf("%d%d",&a,&b);
            printf("%lld\n",query(a,b,1,n,1));
        }
        else
        {
            scanf("%d%d%d",&a,&b,&c);
            update(a,b,c,1,n,1);
        }
    }
    return 0;
}