You are visiting a farm that has a single row of fruit trees arranged from left to right. The trees are represented by an integer array fruits where fruits[i] is the type of fruit the ith tree produces.

You want to collect as much fruit as possible. However, the owner has some strict rules that you must follow:

• You only have two baskets, and each basket can only hold a single type of fruit. There is no limit on the amount of fruit each basket can hold.
• Starting from any tree of your choice, you must pick exactly one fruit from every tree (including the start tree) while moving to the right. The picked fruits must fit in one of your baskets.
• Once you reach a tree with fruit that cannot fit in your baskets, you must stop.

Given the integer array fruits, return the maximum number of fruits you can pick.

Example

Input: fruits = [1,2,1]
Output: 3
Explanation: We can pick from all 3 trees.

Solution

/**
 * @param {number[]} fruits
 * @return {number}
 */
const totalFruit = array => {
    //Create a map to store the current fruit and the count
    let map = new Map(), max = -1
    //Loop through the array
    for(let start = 0, end = 0; end < array.length; end++){
        //Get the current element
        let currElement = array[end]
        //Set the current element in the map
        map.set(currElement, map.get(currElement)+1 || 1 )
        //Check if the map size is greater than 2
        while(map.size > 2){
            //Get the current element
            let char = array[start]
            //Get the current element count
            let charCount = map.get(char)
            //Check if the count is 1
            if(charCount-1 === 0)map.delete(char)
            //Decrement the count
            else map.set(char, charCount-1)
            //Increment the start
            start++
        }
        //Check if the map size is greater than 1
        if(map.size >= 1)max = Math.max(max, end + 1 - start)
    }
    //Return max
    return max
};