Maximum number of mangoes that can be bought
Given two integers W and C, representing the number of watermelons and coins, the task is to find the maximum number of mangoes that can be bought given that each mango costs 1 watermelon and X coins and y coins can be earned selling a watermelon.
Input: W = 10, C = 10, X = 1, Y = 1
Explanation: The most optimal way is to use 10 watermelons and 10 coins to buy 10 mangoes. Hence, the maximum number of mangoes that can be bought is 10.
Input: W = 4, C = 8, X = 4, Y = 4
Explanation: The most optimal way is to sell one watermelon. Then, the number of coins increases by 4. Therefore, the total number of coins becomes 12. Therefore, 3 watermelons and 12 coins can be used to buy 3 mangoes. Hence, the maximum number of mangoes that can be bought is 3.
Approach: This problem can be solved using binary search. The idea is to find the maximum number of mangoes in the search space. Follow the steps below to solve the problem:
- Initialize a variable ans as 0 to store the required result.
- Initialize two variables l as 0, r as W to store the boundary regions of the search space for binary search.
- Loop while l≤r and perform the following steps:
- Store the middle value in a variable mid as (l+r)/2.
- Check if mid number of mangoes can be bought using the given value of W, C, x, and y.
- If true, then update ans to mid and search in the right part of mid by updating l to mid+1. Otherwise, update the value of r to mid-1.
- Print the value of ans as the result.
Below is the implementation of the above approach:
Time Complexity: O(log(W))
Auxiliary Space: O(1)
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