wenbao与树状数组

 1 #include <iostream>
 2 #include <stdio.h>
 3 #include <string.h>
 4 using namespace std;
 5 
 6 int n,aa[50005],cc[50005];
 7 
 8 int lowbit(int x)
 9 {
10     return x&(-x);
11 }
12 
13 void add(int x,int y)
14 {
15     while(x<=n)
16     {
17         cc[x]+=y;
18         x+=lowbit(x);
19     }
20 }
21 
22 int sum(int x)
23 {
24     int s=0;
25     while(x>0)
26     {
27         s+=cc[x];
28         x-=lowbit(x);
29     }
30     return s;
31 }
32 
33 int main()
34 {
35     int t,countn=1;
36     char str[20];
37     scanf("%d",&t);
38     while(t--)
39     {
40         memset(aa,0,sizeof(aa));
41         memset(cc,0,sizeof(cc));
42         scanf("%d",&n);
43         for(int i=1;i<=n;i++)
44         {
45             scanf("%d",&aa[i]);
46             add(i,aa[i]);
47         }
48         printf("Case %d:\n",countn);
49         while(~scanf("%s",str))
50         {
51             if(str[0]==‘E‘)
52                 break;
53             if(str[0]==‘A‘)
54             {
55                 int a,b;
56                 scanf("%d%d",&a,&b);
57                 add(a,b);
58             }
59             if(str[0]==‘Q‘)
60             {
61                 int a,b;
62                 scanf("%d%d",&a,&b);
63                 printf("%d\n",sum(b)-sum(a-1));
64             }
65             if(str[0]==‘S‘)
66             {
67                 int a,b;
68                 scanf("%d%d",&a,&b);
69                 add(a,-b);
70             }
71         }
72         countn++;
73     }
74     return 0;
75 }