线段树--codevs 1690 开关灯

 1 /*没什么好说的，线段树的区间修改加区间查询*/
 2 #define N 100100
 3 #include<iostream>
 4 using namespace std;
 5 #include<cstdio>
 6 #include<cstring>
 7 struct Tree{
 8     int sum,delta,l,r;
 9 }tree[N*4];
10 int n,m,a,x,y;
11 void update(int k)
12 {
13     int lch=k<<1,rch=(k<<1)+1;
14     tree[k].sum=tree[lch].sum+tree[rch].sum;
15 }
16 void build_tree(int k,int l,int r)
17 {
18     tree[k].l=l;tree[k].r=r;
19     if(l==r)
20     {
21         tree[k].sum=tree[k].delta=0;
22         return ;
23     }
24     int mid=(l+r)>>1,lch=k<<1,rch=(k<<1)+1;
25     build_tree(lch,l,mid);
26     build_tree(rch,mid+1,r);
27     update(k);
28  }
29 void down(int k)
30 {
31     int lch=k<<1,rch=(k<<1)+1;
32     tree[lch].delta+=tree[k].delta;
33     tree[lch].delta%=2;
34     tree[lch].sum=(tree[lch].r-tree[lch].l+1)-tree[lch].sum;
35     tree[rch].delta+=tree[k].delta;
36     tree[rch].delta%=2;
37     tree[rch].sum=(tree[rch].r-tree[rch].l+1)-tree[rch].sum;
38     tree[k].delta=0;
39 }
40 void change(int k,int l,int r,int x,int y)
41 {
42     if(x<=l&&r<=y)
43     {
44         tree[k].delta++;
45         tree[k].delta%=2;
46         tree[k].sum=(r-l+1)-tree[k].sum;
47         return;
48     }
49     if(tree[k].delta)
50       down(k);
51     int mid=(l+r)>>1,lch=k<<1,rch=(k<<1)+1;
52     if(x<=mid)
53       change(lch,l,mid,x,y);
54     if(y>mid)
55       change(rch,mid+1,r,x,y);
56     update(k);
57 }
58 int query(int k,int l,int r,int x,int y)
59 {
60     if(x<=l&&r<=y)
61     {
62         return tree[k].sum;
63     }
64     if(tree[k].delta)
65       down(k);
66     int mid=(l+r)>>1,lch=k<<1,rch=(k<<1)+1;
67     int ans=0;
68     if(x<=mid)
69       ans+=query(lch,l,mid,x,y);
70     if(y>mid)
71       ans+=query(rch,mid+1,r,x,y);
72     return ans;  
73 }
74 int main()
75 {
76     scanf("%d%d",&n,&m);
77     build_tree(1,1,n);
78     for(int i=1;i<=m;++i)
79     {
80         scanf("%d%d%d",&a,&x,&y);
81         if(a==0)
82         {
83             change(1,1,n,x,y);
84         }
85         else printf("%d\n",query(1,1,n,x,y));
86     }
87     return 0;
88 }