Google search results: How to find the minimum window that contains all the search keywords?

Question

What is the complexity of the algorithm is that is used to find the smallest snippet that contains all the search key words?

Answer 1

For all the words, maintain min and max index in case there is going to be more than one entry; if not both min and mix index will same.

import edu.princeton.cs.algs4.ST;

public class DicMN {

    ST st = new ST<>();

    public class Words {
        int min;
        int max;
        public Words(int index) {
            min = index;
            max = index;
        }
    }

    public int findMinInterval(String[] sw) {

        int begin = Integer.MAX_VALUE;
        int end = Integer.MIN_VALUE;
        for (int i = 0; i < sw.length; i++) {
            if (st.contains(sw[i])) {
                Words w = st.get(sw[i]);
                begin = Math.min(begin, w.min);
                end = Math.max(end, w.max);
            }
        }

        if (begin != Integer.MAX_VALUE) {
            return (end - begin) + 1;
        }
        return 0;
    }

    public void put(String[] dw) {

        for (int i = 0; i < dw.length; i++) {
            if (!st.contains(dw[i])) {
                st.put(dw[i], new Words(i));
            }
            else {
                Words w = st.get(dw[i]);
                w.min = Math.min(w.min, i);
                w.max = Math.max(w.max, i);
            }
        }
    }

    public static void main(String[] args) {

        // TODO Auto-generated method stub
        DicMN dic = new DicMN();
        String[] arr1 = { "one", "two", "three", "four", "five", "six", "seven", "eight" };
        dic.put(arr1);
        String[] arr2 = { "two", "five" };
        System.out.print("Interval:" + dic.findMinInterval(arr2));
    }
}