[POJ3468]A Simple Problem with Integers

题目链接：http://poj.org/problem?id=3468

线段树区间更新查询的样题，注意数据范围。连要更新的数据也必须是long long。

 1 #include <algorithm>
 2 #include <iostream>
 3 #include <iomanip>
 4 #include <cstring>
 5 #include <climits>
 6 #include <complex>
 7 #include <cassert>
 8 #include <cstdio>
 9 #include <bitset>
10 #include <vector>
11 #include <deque>
12 #include <queue>
13 #include <stack>
14 #include <ctime>
15 #include <set>
16 #include <map>
17 #include <cmath>
18 using namespace std;
19 
20 typedef long long LL;
21 #define lrt rt << 1
22 #define rrt rt << 1 | 1
23 const int maxn = 100100;
24 LL sum[maxn<<2], add[maxn<<2];
25 int n, q;
26 char cmd[2];
27 
28 void pushUP(int rt) {
29     sum[rt] = sum[lrt] + sum[rrt];
30 }
31 
32 void pushDOWN(int rt, int len) {
33     if(add[rt]) {
34         sum[lrt] += (len - len / 2) * add[rt];
35         sum[rrt] += len / 2 * add[rt];
36         add[lrt] += add[rt];
37         add[rrt] += add[rt];
38         add[rt] = 0;
39     }
40 }
41 
42 void build(int l, int r, int rt) {
43     add[rt] = 0;
44     if(l == r) {
45         scanf("%I64d", &sum[rt]);
46         return;
47     }
48     int mid = (l + r) >> 1;
49     build(l, mid, lrt);
50     build(mid+1, r, rrt);
51     pushUP(rt);
52 }
53 
54 void update(int L, int R, LL c, int l, int r, int rt) {
55     if(L <= l && r <= R) {
56         add[rt] += c;
57         sum[rt] += (LL)c * (r - l + 1);
58         return;
59     }
60     pushDOWN(rt, r-l+1);
61     int mid = (l + r) >> 1;
62     if(L <= mid) update(L, R, c, l, mid, lrt);
63     if(mid < R) update(L, R, c, mid+1, r, rrt);
64     pushUP(rt);
65 }
66 
67 LL query(int L, int R, int l, int r, int rt) {
68     if(L <= l && r <= R) return sum[rt];
69     pushDOWN(rt, r-l+1);
70     int mid = (l + r) >> 1;
71     LL ret = 0;
72     if(L <= mid) ret += query(L, R, l, mid, lrt);
73     if(mid < R) ret += query(L, R, mid+1, r, rrt);
74     return ret;
75 }
76 
77 int main() {
78     // freopen("in", "r", stdin);
79     int l, r, c;
80     while(~scanf("%d%d",&n,&q)) {
81         build(1, n, 1);
82         while(q--) {
83             scanf("%s", cmd);
84             if(cmd[0] == 'Q') {
85                 scanf("%d%d",&l,&r);
86                 printf("%I64d\n", query(l,r,1,n,1));
87             }
88             else {
89                 scanf("%d%d%d",&l,&r,&c);
90                 update(l,r,LL(c),1,n,1);
91             }
92         }
93     }
94     return 0;
95 }

 

posted @ 2015-08-30 22:14  Kirai  阅读(192)  评论(0)  编辑  收藏  举报