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bzoj - 1007

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 1 #include <algorithm>
 2 #include <cstring>
 3 #include <cstdio>
 4 #include <bitset>
 5 #include <vector>
 6 #include <queue>
 7 #include <stack>
 8 #include <cmath>
 9 #include <list>
10 #include <set>
11 #include <map>
12 #define rep(i,a,b) for(int i = a;i <= b;++ i)
13 #define per(i,a,b) for(int i = a;i >= b;-- i)
14 #define mem(a,b) memset((a),(b),sizeof((a)))
15 #define FIN freopen("in.txt","r",stdin)
16 #define FOUT freopen("out.txt","w",stdout)
17 #define IO ios_base::sync_with_stdio(0),cin.tie(0)
18 #define mid ((l+r)>>1)
19 #define ls (id<<1)
20 #define rs ((id<<1)|1)
21 #define N 50005
22 #define INF 0x3f3f3f3f
23 #define INFF ((1LL<<62)-1)
24 #define mod 998244353
25 typedef long long ll;
26 using namespace std;
27   
28 int n,q[N],ans[N]; // q[n] = [l, r);
29 struct Node{
30     int a,b,id;
31     bool operator < (const Node &r) const {
32         if(a == r.a)    return b > r.b;
33         return a < r.a;
34     }
35 }node[N];
36 double cal(int x, int y){
37     double ans = (node[y].b-node[x].b)*1.0/(node[x].a-node[y].a);
38     return ans;
39 }
40 int main()
41 {IO;
42     //FIN;
43     while(cin >> n){
44         rep(i, 1, n)    { cin >> node[i].a >> node[i].b; node[i].id = i; }
45         sort(node+1, node+n+1);
46         int top = 0;
47         rep(i, 1, n){
48             if(top >= 2){
49                 while(top >= 2){
50                     double x = cal(i, q[top-1]), X = cal(q[top-1], q[top-2]);
51                     if(x <= X)   top--;
52                     else
53                         break;
54                 }
55             }
56             q[top++] = i;
57         }
58         int len = 0;
59         rep(i, 0, top-1)    ans[len++] = node[q[i]].id;
60         sort(ans, ans+len);
61         rep(i, 0, len-1)    cout << ans[i] << " ";
62     }
63     return 0;
64 }
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bzoj - 1007