poj 3468 线段树成段加减
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 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>
#define lson l,m,2*rt
#define rson m+1,r,2*rt+1
using namespace std;
const int maxn = 100005;
long long tree[maxn*4];
long long add[maxn*4];
void pushUp(int rt)
{
tree[rt]=tree[rt*2]+tree[rt*2+1];
}
void pushDown(int rt,int ln,int rn)
{
if(add[rt])
{
add[rt*2]+=add[rt];
add[rt*2+1]+=add[rt];
tree[rt*2]+=add[rt]*ln;
tree[rt*2+1]+=add[rt]*rn;
add[rt]=0;
}
}
void build(int l,int r,int rt)
{
add[rt]=0;
if(l==r)
{
scanf("%lld",&tree[rt]);
return;
}
int m=(l+r)/2;
build(lson);
build(rson);
pushUp(rt);
}
long long query(int L,int R,int l,int r,int rt)
{
if(L<=l&&r<=R)
return tree[rt];
int m=(l+r)/2;
pushDown(rt,m-l+1,r-m);
long long res=0;
if(L<=m)
res+=query(L,R,lson);
if(R>m)
res+=query(L,R,rson);
return res;
}
void update(int L,int R,int c,int l,int r,int rt)
{
if(L<=l&&r<=R)
{
tree[rt]+=(r-l+1)*c;
add[rt]+=c;
return;
}
int m=(l+r)/2;
pushDown(rt,m-l+1,r-m);
if(L<=m)
update(L,R,c,lson);
if(R>m)
update(L,R,c,rson);
pushUp(rt);
}
int main()
{
int n,m;
cin >> n >> m;
build(1,n,1);
char c;
int a,b,d;
while(m--)
{
cin >> c;
if(c=='Q')
{
cin >> a >> b;
cout << query(a,b,1,n,1) << endl;
}
else
{
cin >> a >> b >> d;
update(a,b,d,1,n,1);
}
}
return 0;
}

浙公网安备 33010602011771号