1 #include <stdio.h>
2 #include <bitset>
3 #include <string.h>
4 #include <stack>
5 #include <algorithm>
6 #include <iostream>
7 #include <set>
8 #include <map>
9 #include <math.h>
10 #include <queue>
11 #include <complex>
12 using namespace std ;
13 typedef long long ll ;
14 typedef long double ld ;
15 typedef unsigned long long ull ;
16 #ifdef _WIN32
17 #define LLD "%I64d"
18 #else
19 #define LLD "%lld"
20 #endif
21 #define pi (acos(-1.0))
22 #define fi first
23 #define se second
24 #define lson (o<<1),l,mid
25 #define rson (o<<1|1),mid+1,r
26 #define MP make_pair
27 #define sqr(x) ((x)*(x))
28 #define ALL(v) (v).begin(),(v).end()
29 #define showtime fprintf(stderr,"time = %.15f\n",clock() / (double)CLOCKS_PER_SEC)
30 const double eps = 1e-8;
31 const int inf = 0x3f3f3f3f ;
32 const ll INF = (ll)4e18 ;
33 const int MOD=(int)1e9+7,BAS=257,invBAS=70038911;
34 int sign(double x){return x<-eps?-1:x>eps;}
35
36 const int M = 110000 ;
37 struct Point {
38 int id ;
39 double a,b,rate,x,y ;
40 inline void minus (Point t) {
41 x-=t.x ; y-=t.y ;
42 }
43 inline double mul (Point t) {
44 return x*t.y-y*t.x ;
45 }
46 inline bool operator < (const Point &t) {
47 if (sign(x-t.x)==0) return y>t.y ;
48 return x<t.x ;
49 }
50 } p[M] , c[M] ;
51 int n , st[M] , sz ;
52 double money[M] ;
53
54 double slope (Point e,Point t,Point g) {
55 e.minus(g) ; t.minus(g) ;
56 return sign(t.mul(e))<=0 ;
57 }
58
59 double get (int i,int j) {
60 return p[i].x*p[j].b+p[i].y*p[j].a ;
61 }
62
63 void cdq (int l,int r) {
64 if (l == r) {
65 money[l] = max(money[l-1],money[l]) ;
66 p[l].x = money[l]/(p[l].a*p[l].rate+p[l].b) ;
67 p[l].y = p[l].x*p[l].rate ;
68 return ;
69 }
70 int mid = l+r>>1 ;
71 for (int i=l,j=0,k=1; i<=r ; i ++)
72 if (p[i].id<=mid) c[l+j++] = p[i] ;
73 else c[mid+k++] = p[i] ;
74 memcpy (p+l,c+l,sizeof(Point)*(r-l+1)) ;
75 cdq (l,mid) ;
76 sz = 0 ;
77 for (int i=l ; i<=mid ; i++) {
78 if (sz && sign(p[st[sz-1]].x-p[i].x)==0) continue ;
79 while (sz>1&&slope(p[st[sz-2]],p[st[sz-1]],p[i]))sz --;
80 st[sz++] = i ;
81 }
82 for (int i=mid+1 ; i<=r ; i++) {
83 while (sz>1 && sign(get(st[sz-2],i)-get(st[sz-1],i))>0) sz -- ;
84 money[p[i].id] = max (money[p[i].id] , get(st[sz-1],i)) ;
85 }
86 cdq (mid+1,r) ;
87 int e=l , t=mid+1 ;
88 for (int i=l ; i<=r ; i++)
89 if (e<=mid && (t>r || p[e]<p[t])) c[i] = p[e++] ;
90 else c[i] = p[t++] ;
91 memcpy(p+l,c+l,sizeof(Point)*(r-l+1)) ;
92 }
93
94 bool cmp (const Point &e , const Point &t) { return e.b*t.a>t.b*e.a ; }
95
96 int main () {
97 scanf ("%d%lf" , &n , money) ;
98 for (int i=0 ; i<n ; i ++) {
99 scanf ("%lf%lf%lf" , &p[i].a,&p[i].b,&p[i].rate);
100 p[i].id = i ;
101 }
102 sort (p,p+n,cmp) ;
103 cdq (0,n-1) ;
104 printf ("%.3f\n" , money[n-1]) ;
105 return 0 ;
106 }
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