BZOJ1595 [Usaco2008 Jan]人工湖

直接模拟。。。从最低的开始向两边拓展= =

 1 /**************************************************************
 2     Problem: 1595
 3     User: rausen
 4     Language: C++
 5     Result: Accepted
 6     Time:328 ms
 7     Memory:3932 kb
 8 ****************************************************************/
 9
10 #include <cstdio>
11
12 using namespace std;
13 typedef long long ll;
14 const int N = 1e5 + 5;
15 const ll inf = (ll) 1e18;
16
17 inline int read();
18
19 struct data {
20     ll w, h;
21     int pre, nxt;
22
23     inline void get(int x) {
24         w = read(), h = read();
25         pre = x - 1, nxt = x + 1;
26     }
27 } a[N];
28
29 int n, now;
30 ll now_ans, ans[N];
31
32 int main() {
33     int i;
34     n = read();
35     for (i = now = 1; i <= n; ++i) {
36         a[i].get(i);
37         if (a[i].h < a[now].h) now = i;
38     }
39     a[0].w = a[n + 1].w = 0, a[0].h = a[n + 1].h = inf, a[0].nxt = 1, a[n + 1].pre = n;
40 #define Pre a[now].pre
41 #define Nxt a[now].nxt
42     for (i = 1; i <= n; ++i) {
43         while (a[Pre].h < a[now].h) now = Pre;
44         while (a[Nxt].h < a[now].h) now = Nxt;
45         ans[now] = now_ans + a[now].w;
46         a[Pre].nxt = Nxt, a[Nxt].pre = Pre;
47         if (a[Pre].h < a[Nxt].h) {
48             now_ans += a[now].w * (a[Pre].h - a[now].h);
49             a[Pre].w += a[now].w, now = Pre;
50         } else {
51             now_ans += a[now].w * (a[Nxt].h - a[now].h);
52             a[Nxt].w += a[now].w, now = Nxt;
53         }
54     }
55     for (i = 1; i <= n; ++i)
56         printf("%lld\n", ans[i]);
57     return 0;
58 }
59
60 inline int read() {
61     static int x;
62     static char ch;
63     x = 0, ch = getchar();
64     while (ch < ‘0‘ || ‘9‘ < ch)
65         ch = getchar();
66     while (‘0‘ <= ch && ch <= ‘9‘) {
67         x = x * 10 + ch - ‘0‘;
68         ch = getchar();
69     }
70     return x;
71 }