CodeForces-Round524 A~D

　　　　　　　　　　　　　　　　　　　　　　　　　　A. Petya and Origami

　　　　　　　　　　　　　　　　　　　　　　　　

time limit per test 

1 second

　　　　　　　　　　　　　　　　　　

 

　　　　　　　　　　　　　　　　　　　　　　　　memory limit per test 

256 megabytes

input

standard input

output

standard output

Petya is having a party soon, and he has decided to invite his n friends.

He wants to make invitations in the form of origami. For each invitation, he needs two red sheets, five green sheets, and eight blue sheets. The store sells an infinite number of notebooks of each color, but each notebook consists of only one color with k sheets of either red, green, or blue.

Find the minimum number of notebooks that Petya needs to buy to invite all n of his friends.

Input

The first line contains two integers 1≤n,k≤108) — the number of Petya's friends and the number of sheets in each notebook respectively.

Output

Print one number — the minimum number of notebooks that Petya needs to buy.

Examples

input

3 5

output

10

input

15 6

output

38

In the first example, we need 5 blue notebooks.

In the second example, we need 20 blue notebooks.

 

题解：水题；向上取证即可；

参考代码：

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 #define cls(x, val) memset(x,val,sizeof(x))
 4 typedef long long ll;
 5 typedef unsigned long long ull;
 6 const int INf=0x3f3f3f3f;
 7 double n,k,n1,n2,n3;
 8 int main()
 9 {
10     scanf("%lf%lf",&n,&k);
11     n1=2*n,n2=5*n,n3=8*n;
12     int sum=ceil(n1/k)+ceil(n2/k)+ceil(n3/k);
13     printf("%d\n",sum);
14     
15     return 0;
16 } 

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