POJ 3468 A Simple Problem with Integers 线段树 区间更新

 #include<iostream>
 #include<string>
 #include<algorithm>
 #include<cstdlib>
 #include<cstdio>
 #include<set>
 #include<map>
 #include<vector>
 #include<cstring>
 #include<stack>
 #include<cmath>
 #include<queue>
 //#include <bits/stdc++.h>
 using namespace std;
 #define LL long long
 const int maxn=;
 struct node
 {
     LL sum,val;
 }tree[maxn*];

 void pushup(int rt)
 {
     tree[rt].sum=tree[rt<<].sum+tree[rt<<|].sum;
 }
 void pushdown(int rt,int m)
 {
     if(tree[rt].val)
     {
         tree[rt<<].val+=tree[rt].val;
         tree[rt<<|].val+=tree[rt].val;
         tree[rt<<].sum+=(LL)(m-(m>>))*tree[rt].val;
         tree[rt<<|].sum+=(LL)(m>>)*tree[rt].val;
         tree[rt].val=;
     }
 }

 void build_tree(int l,int r,int rt)
 {
     tree[rt].val=;
     if(l==r)
     {
         scanf("%I64d",&tree[rt].sum);
         return ;
     }
     int m=(l+r)>>;
     build_tree(l,m,rt<<);
     build_tree(m+,r,rt<<|);
     pushup(rt);
 }

 LL query(int L,int R,int l,int r,int rt)
 {
     if(L<=l&&r<=R)
     {
         return tree[rt].sum;
     }
     int m=(l+r)>>;
     pushdown(rt,r-l+);
     LL ans=;
     if(L<=m)
         ans+=query(L,R,l,m,rt<<);
     if(m<R)
         ans+=query(L,R,m+,r,rt<<|);
     pushup(rt);
     return ans;
 }

 void update(int L,int R,int add,int l,int r,int rt)
 {
     if(L<=l&&r<=R)
     {
         tree[rt].sum+=(LL)add*(r-l+);
         tree[rt].val+=add;
         return;
     }
     pushdown(rt,r-l+);
     int m=(l+r)>>;
     if(L<=m)
         update(L,R,add,l,m,rt<<);
     if(R>m)
         update(L,R,add,m+,r,rt<<|);
     pushup(rt);
 }

 int main()
 {
     int n,a,b,q;
     LL c;
     while(~scanf("%d%d",&n,&q))
     {
         build_tree(,n,);
         char s[];
         while(q--)
         {
             scanf("%s",s);
             if(s[]=='Q')
             {
                 cin>>a>>b;
                 cout<<query(a,b,,n,)<<endl;
             }
             else if(s[]=='C')
             {
                 cin>>a>>b>>c;
                 update(a,b,c,,n,);
             }
         }
     }
     return ;
 }