树状数组HDU1166

http://acm.hdu.edu.cn/showproblem.php?pid=1166

 #include<stdio.h>
 #include<string.h>
 int c[];
 int n;
 int lowbit(int x)
 {
     return x&(-x);
 }

 void add(int i,int x){
 while(i<=n){
     c[i]+=x;
     i+=lowbit(i);
 }
 }
 void sub(int i,int x){
 while(i<=n){
       c[i]-=x;
       i+=lowbit(i);
       }
     }
 int sum(int i)
 {
     int s=;
     while(i>){
         s+=c[i];
         i-=lowbit(i);
     }
     return s;
 }
 int main()
 {
     int a,b,x;
     char s[];
     int t;
    scanf("%d",&t);
     int time=;
     while(t--){
             time++;
             printf("Case %d:\n",time);
 memset(c,,sizeof(c));
            scanf("%d",&n);
     for(int i=;i<=n;i++){
         scanf("%d",&x);
         add(i,x);
     }
     while(~scanf("%s",&s)&&strcmp(s,"End")!=){scanf("%d%d",&a,&b);
        if(s[]=='A'){

         add(a,b);
        }
       if(s[]=='Q'){
 int f=sum(b)-sum(a-);
         printf("%d\n",f);
        }
      if(s[]=='S'){
         sub(a,b);
        }

     }
     }
 }

注意呦，同样的代码用c++提交就超时喽……