hdu1166(树状数组入门）

#include <iostream>
#include <cstdio>
#include <cstring>
#define M 10
using namespace std;
const int MAX = 50010;
int a[MAX], c[MAX];
int n;
int lowbit(int x){
   return x&(-x);
}

int sum(int len){
   int temp = len;
   int result = 0;
   while(temp>0){
      result = result + c[temp];
      temp = temp - lowbit(temp);
   }
   return result;
}

void get_result(int from, int to){
   int temp1 = sum(from - 1);
   int temp2 = sum(to);
   int t = temp2 - temp1;
   printf("%d\n", t);
}

void update(int x, int value){
    while(x <= n){
    c[x] = c[x] + value;
    x = x + lowbit(x);
    }
}

int init(int n) {
   for (int i = 0; i <= n; i++) {
      a[i] = 0;
      c[i] = 0;
   }
   return 0;
}

int main()
{
    int T, loc, temp;
    char tem[M];
    scanf("%d", &T);
    for(int k = 1; k <= T; k++) {
      printf("Case %d:\n", k);
      scanf("%d", &n);
      init(n);

      for(int j = 1; j <= n; j++){
         scanf("%d", &a[j]);
         update(j, a[j]);
      }
      while(scanf("%s", tem)!=EOF && tem[0] != 'E'){
         scanf("%d%d", &loc, &temp);
         switch(tem[0]){
           case 'Q': get_result(loc, temp); break;
           case 'A': update(loc, temp); break;
           case 'S': update(loc, temp*(-1)); break;
         }
      }
    }
    return 0;
}
/********************
10
10
1 2 3 4 5 6 7 8 9 10
Query 1 3
Add 3 6
Query 2 7
Sub 10 2
Add 6 3
Query 3 10
End
******************/