Karl loves playing games on social networking sites. His current favorite is CandyMaker, where the goal is to make candies.
Karl just started a level in which he must accumulate candies starting with machines and workers. In a single pass, he can make candies. After each pass, he can decide whether to spend some of his candies to buy more machines or hire more workers. Buying a machine or hiring a worker costs units, and there is no limit to the number of machines he can own or workers he can employ.
Karl wants to minimize the number of passes to obtain the required number of candies at the end of a day. Determine that number of passes.
For example, Karl starts with machine and workers. The cost to purchase or hire, and he needs to accumulate candies. He executes the following strategy:
- Make candies. Purchase two machines.
- Make candies. Purchase machines and hire workers.
- Make candies. Retain all candies.
- Make candies. With yesterday's production, Karl has candies.
It took passes to make enough candies.
Function Description
Complete the minimumPasses function in the editor below. The function must return a long integer representing the minimum number of passes required.
minimumPasses has the following parameter(s):
- m: long integer, the starting number of machines
- w: long integer, the starting number of workers
- p: long integer, the cost of a new hire or a new machine
- n: long integer, the number of candies to produce
Input Format
A single line consisting of four space-separated integers describing the values of , , , and , the starting number of machines and workers, the cost of a new machine or a new hire, and the the number of candies Karl must accumulate to complete the level.
Constraints
Output Format
Return a long integer denoting the minimum number of passes required to accumulate at least candies.
Sample Input
3 1 2 12
Sample Output
3
Explanation
Karl makes three passes:
- In the first pass, he makes candies. He then spends of them hiring another worker, so and he has one candy left over.
- In the second pass, he makes candies. He spends of them on another machine and another worker, so and and he has candies left over.
- In the third pass, Karl makes candies. Because this satisfies his goal of making at least candies, we print the number of passes (i.e., ) as our answer.