1268. Search Suggestions System

Given an array of strings 

products

 and a string 

searchWord

. We want to design a system that suggests at most three product names from 

products

 after each character of 

searchWord

 is typed. Suggested products should have common prefix with the searchWord. If there are more than three products with a common prefix return the three lexicographically minimums products.

Return list of lists of the suggested 

products

searchWord

 is typed. 

Example 1:

Input: products = ["mobile","mouse","moneypot","monitor","mousepad"], searchWord = "mouse"
Output: [
["mobile","moneypot","monitor"],
["mobile","moneypot","monitor"],
["mouse","mousepad"],
["mouse","mousepad"],
["mouse","mousepad"]
]
Explanation: products sorted lexicographically = ["mobile","moneypot","monitor","mouse","mousepad"]
After typing m and mo all products match and we show user ["mobile","moneypot","monitor"]
After typing mou, mous and mouse the system suggests ["mouse","mousepad"]
      

Example 2:

Input: products = ["havana"], searchWord = "havana"
Output: [["havana"],["havana"],["havana"],["havana"],["havana"],["havana"]]
      

Example 3:

Input: products = ["bags","baggage","banner","box","cloths"], searchWord = "bags"
Output: [["baggage","bags","banner"],["baggage","bags","banner"],["baggage","bags"],["bags"]]
      

Example 4:

Input: products = ["havana"], searchWord = "tatiana"
Output: [[],[],[],[],[],[],[]]
      

• 1 <= products.length <= 1000

• There are no repeated elements in 

  products

  .

• 1 <= Σ products[i].length <= 2 * 10^4

• All characters of 

  products[i]

   are lower-case English letters.

• 1 <= searchWord.length <= 1000

• searchWord

class Solution {
    public List<List<String>> suggestedProducts(String[] products, String searchWord) {
        List<List<String>> results = new ArrayList<>();

        if(products == null || products.length == 0) return results;

        // sort the products lexicographically
        Arrays.sort(products);

        for(int i = 1; i <= searchWord.length(); i++) {
            List<String> temp = new ArrayList<>();
            int count = 0;
            for(String product : products) {
                if(product.length() >= i && product.substring(0, i).equals(searchWord.substring(0, i))) {
                    temp.add(product);
                    count++;
                    if(count >= 3) {
                        break;
                    }
                }
            }
            results.add(temp);
        }

        return results;
    }
}