There are $n$ pairwise-distinct points and a line $x+y=k$ on a two-dimensional plane. The $i$-th point is at $(x_i,y_i)$. All points have non-negative coordinates and are strictly below the line. Alternatively, $0 \leq x_i,y_i, x_i+y_i \lt k$.
Tenzing wants to erase all the points. He can perform the following two operations:
- Draw triangle: Tenzing will choose two non-negative integers
$a$,$b$that satisfy$a+b \lt k$, then all points inside the triangle formed by lines$x=a$,$y=b$and$x+y=k$will be erased. It can be shown that this triangle is an isosceles right triangle. Let the side lengths of the triangle be$l$,$l$and$\sqrt 2 l$respectively. Then, the cost of this operation is$l \cdot A$.The blue area of the following picture describes the triangle with$a=1,b=1$with cost$=1\cdot A$.
- Erase a specific point: Tenzing will choose an integer
$i$that satisfies$1 \leq i \leq n$and erase the point$i$. The cost of this operation is$c_i$.
Help Tenzing find the minimum cost to erase all of the points.
Input
The first line of the input contains three integers $n$, $k$ and $A$ ($1\leq n,k\leq 2\cdot 10^5$, $1\leq A\leq 10^4$) — the number of points, the coefficient describing the hypotenuse of the triangle and the coefficient describing the cost of drawing a triangle.
The following $n$ lines of the input the $i$-th line contains three integers $x_i,y_i,c_i$ ($0\leq x_i,y_i,x_i+y_i \lt k$, $1\leq c_i\leq 10^4$) — the coordinate of the $i$-th points and the cost of erasing it using the second operation. It is guaranteed that the coordinates are pairwise distinct.
Output
Output a single integer —the minimum cost needed to erase all of the points.
Note
The picture of the first example:
Tenzing do the following operations:
- draw a triangle with
$a=3,b=2$, the cost$=1\cdot A=1$. - erase the first point, the cost
$=1$. - erase the second point, the cost
$=1$. - erase the third point, the cost
$=1$.

The picture of the second example:

样例
4 6 1
1 2 1
2 1 1
1 1 1
3 2 6
4
6 7 1
4 2 1
3 3 1
5 1 4
3 2 5
4 1 1
0 6 4
4
10 4 100
0 0 1
0 1 1
0 2 50
0 3 200
1 0 1
1 1 1
1 2 1
2 0 200
2 1 200
3 0 200
355
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