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线段树 区间查询区间修改 poj 3468

 1 #include<cstdio>
 2 #include<iostream>
 3 #include<algorithm>
 4 #include<string.h>
 5 using namespace std;
 6 typedef long long ll;
 7 const ll maxn=1e5+10;
 8 ll ary[maxn];
 9 struct node
10 {
11     ll l,r,val;
12     ll add;
13 }tree[maxn<<2];
14 void pushup(ll cur)
15 {
16     tree[cur].val=tree[cur<<1].val+tree[cur<<1|1].val;
17 }
18 void down(ll cur,ll len)
19 {
20     if(tree[cur].add){
21         tree[cur<<1].val+=(len-(len>>1))*tree[cur].add;
22         tree[cur<<1|1].val+=(len>>1)*tree[cur].add;
23         tree[cur<<1].add+=tree[cur].add;
24         tree[cur<<1|1].add+=tree[cur].add;
25         tree[cur].add=0;
26     }
27 }
28 void build(ll l,ll r,ll cur)
29 {
30     tree[cur].l=l,tree[cur].r=r;
31     tree[cur].val=tree[cur].add=0;
32     if(l==r){
33         tree[cur].val=ary[l];
34         return;
35     }
36     ll mid=(l+r)/2;
37     build(l,mid,cur<<1);
38     build(mid+1,r,cur<<1|1);
39     pushup(cur);
40 }
41 ll query(ll l,ll r,ll cur)
42 {
43     ll L=tree[cur].l,R=tree[cur].r;
44     if(l<=L&&r>=R) return tree[cur].val;
45     down(cur,R-L+1);
46     ll mid=(L+R)/2;
47     ll ans=0;
48     if(l<=mid) ans+=query(l,r,cur<<1);
49     if(r>mid)  ans+=query(l,r,cur<<1|1);
50     return ans;
51 }
52 void update(ll l,ll r,ll key,ll cur)
53 {
54     ll L=tree[cur].l,R=tree[cur].r;
55     if(l<=L&&r>=R){
56         tree[cur].val+=(R-L+1)*key;
57         tree[cur].add+=key;
58         return;
59     }
60     down(cur,R-L+1);
61     ll mid=(L+R)/2;
62     if(l<=mid) update(l,r,key,cur<<1);
63     if(r>mid)  update(l,r,key,cur<<1|1);
64     pushup(cur);
65 }
66 int main()
67 {
68     ll n,m;
69     scanf("%lld%lld",&n,&m);
70     for(ll i=1;i<=n;i++)
71         scanf("%lld",&ary[i]);
72     build(1,n,1);
73     while(m--){
74         char tmp;
75         cin>>tmp;
76         if(tmp==Q){
77             ll l,r;
78             scanf("%lld%lld",&l,&r);
79             ll ans=query(l,r,1);
80             printf("%lld\n",ans);
81         }
82         else{
83             ll l,r,key;
84             scanf("%lld%lld%lld",&l,&r,&key);
85             update(l,r,key,1);
86         }
87     }
88     return 0;
89 }

 

时间:2019-09-11 22:49:44阅读(10)
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