hdu1166 敌兵布阵

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 const int N = 50005;
 4 int a[N], tree[N * 4], n;
 5 
 6 void build(int num, int l, int r)
 7 {
 8     if (l == r) { tree[num] = a[l]; return; }
 9     int m = l + r >> 1;
10     build(num * 2, l, m);
11     build(num * 2 + 1, m + 1, r);
12     tree[num] = tree[num * 2] + tree[num * 2 + 1];
13 }
14 
15 void update(int num, int l, int r, int x, int dx)
16 {
17     if (l == r) { tree[num] += dx; return; }
18     int m = l + r >> 1;
19     if (x <= m) update(num * 2, l, m, x, dx);
20     else update(num * 2 + 1, m + 1, r, x, dx);
21     tree[num] = tree[num * 2] + tree[num * 2 + 1];
22 }
23 
24 int query(int num, int l, int r, int x, int y)
25 {
26     if (x <= l && y >= r) return tree[num];
27     int m = l + r >> 1, ans = 0;
28     if (x <= m) ans += query(num * 2, l, m, x, y);
29     if (y >= m + 1) ans += query(num * 2 + 1, m + 1, r, x, y);
30     return ans;
31 }
32 
33 int main()
34 {
35     ios::sync_with_stdio(false);
36     int T, Kase = 1;
37     cin >> T;
38     while (T--)
39     {
40         cout << "Case " << Kase++ << ":" << endl;
41         cin >> n;
42         for (int i = 1; i <= n; i++) cin >> a[i];
43         build(1, 1, n);
44         string tmp; int a, b;
45         while (cin >> tmp, tmp[0] != ‘E‘)
46         {
47             if (tmp[0] == ‘Q‘) { cin >> a >> b; cout << query(1, 1, n, a, b) << endl; }
48             else if (tmp[0] == ‘A‘) { cin >> a >> b; update(1, 1, n, a, b); }
49             else { cin >> a >> b; update(1, 1, n, a, -b); } 
50         }
51     }
52     return 0;
53 }