kuangbin_SegTree A (HDU 1166)

#include <cstdio>
#include <cstring>
#include <queue>
#include <vector>
#include <algorithm>
#define INF 0x3f3f3f3f
#define lson l, m, root<<1
#define rson m+1, r, root<<1|1
using namespace std;

const int MAXN = 5e4+10;
int sum[MAXN*4];

void pushup(int root)
{
sum[root] = sum[root<<1] + sum[root<<1|1];
}

void build(int l, int r, int root)
{
if(l == r) scanf("%d", &sum[root]);
else{
int m = (l + r) >> 1;
build(lson);
build(rson);
pushup(root);
}
}

void update(int point, int val, int l, int r, int root)
{
if(l == r) sum[root] += val;
else{
int m = (l + r) >> 1;
if(point <= m) update(point, val, lson);
else update(point, val, rson);
pushup(root);
}
}

int query(int L, int R, int l, int r, int root)
{
if(L <= l && R >= r) return sum[root];
int res = 0;
int m = (l + r) >> 1;
if(L <= m) res += query(L, R, lson);
if(R > m) res += query(L, R, rson);
return res;
}

int main()
{
int t, n;
scanf("%d", &t);
for(int kase = 1; kase <= t; kase++){
printf("Case %d:\n", kase);
scanf("%d", &n);
build(1, n, 1);
char op[10];
while(scanf("%s", op), op[0] != 'E'){
int u, v;
scanf("%d%d", &u, &v);
if(op[0] == 'A') update(u, v, 1, n, 1);
else if(op[0] == 'S') update(u, -v, 1, n, 1);
else printf("%d\n", query(u, v, 1, n, 1));
}
}
return 0;
}