[kuangbin带你飞]专题七 线段树 C - A Simple Problem with Integers

#include <cstdio>
#include <algorithm>
#include <iostream>
#define lid (id << 1)
#define rid (id << 1 | 1)
using namespace std;
const int maxn = 1e5+6;
int n,a[maxn],m;
struct node
{
int l,r;
long long sum,lazy;
void updata(long long x)
{
sum =sum+(r-l+1)*x; //增加
lazy=lazy+x;
}
} tr[maxn*4];
void push_up(int id)
{
tr[id].sum=tr[lid].sum+tr[rid].sum;
}
void push_down(int id)
{
if(tr[id].lazy)
{
tr[lid].updata(tr[id].lazy);
tr[rid].updata(tr[id].lazy);
tr[id].lazy=0;
}
}
void build(int id,int l,int r)
{
tr[id].l=l,tr[id].r=r;
if(l==r) tr[id].sum=a[l],tr[id].lazy=0;
else
{
int mid=(l+r)/2;
build(lid,l,mid);
build(rid,mid+1,r);
push_up(id);
}
}
void updata(int id,int l,int r,long long val)
{
if(l==tr[id].l&&tr[id].r==r) tr[id].updata(val);
else
{
push_down(id);
int mid = (tr[id].l+tr[id].r)>>1;
if(r<=mid) updata(lid,l,r,val);
else if (l>mid) updata(rid,l,r,val);
else
{
updata(lid,l,mid,val);
updata(rid,mid+1,r,val);
}
push_up(id);
}
}
long long query_sum(int id,int l,int r)
{
if(l==tr[id].l&&tr[id].r==r) return tr[id].sum;
else
{
push_down(id);
int mid = (tr[id].l+tr[id].r)>>1;
if(r<=mid)  return query_sum(lid,l,r);
else if(l>mid) return query_sum(rid,l,r);
else return query_sum(lid,l,mid)+query_sum(rid,mid+1,r);
push_up(id);
}
}
int main()
{
while(scanf("%d%d",&n,&m)==2)
{
for(int i=1;i<=n;i++) scanf("%d",&a[i]);
build(1,1,n);
char ch;
for(int i=1;i<=m;i++)
{
scanf(" %c",&ch);
if(ch=='Q')
{
int x,y; scanf("%d%d",&x,&y);
printf("%lld\n",query_sum(1,x,y));
}
else if(ch=='C')
{
int val,x,y;
scanf("%d%d%d",&x,&y,&val);
updata(1,x,y,val);
}
}
}
}