Day-27 Find Right Interval

class Solution {
    public int[] findRightInterval(int[][] intervals) {
        int[] res = new int[intervals.length];
        for (int i = 0; i < intervals.length; i++) {
            int min = Integer.MAX_VALUE;
            int minindex = -1;
            for (int j = 0; j < intervals.length; j++) {
                if (intervals[j][0] >= intervals[i][1] && intervals[j][0] < min) {
                    min = intervals[j][0];
                    minindex = j;
                }
            }
            res[i] = minindex;
        }
        return res;
    }
}

class Solution {
    public int[] findRightInterval(int[][] intervals) {
        int[] result = new int[intervals.length];
        TreeMap<Integer, Integer> intervalMap = new TreeMap<>();
         for (int i = 0; i < intervals.length; ++i) {
            intervalMap.put(intervals[i][0], i);    
        }
        
        for (int i = 0; i < intervals.length; ++i) {
            Map.Entry<Integer, Integer> entry = intervalMap.ceilingEntry(intervals[i][1]);
            result[i] = (entry != null) ? entry.getValue() : -1;
        }
        return result;
    }
}


public class Solution {

  public int[] findRightInterval(int[][] intervals) {
    int[][] endIntervals = Arrays.copyOf(intervals, intervals.length);
    HashMap<int[], Integer> hash = new HashMap<>();
    for (int i = 0; i < intervals.length; i++) {
      hash.put(intervals[i], i);
    }
    Arrays.sort(intervals, (a, b) -> a[0] - b[0]);
    Arrays.sort(endIntervals, (a, b) -> a[1] - b[1]);
    int j = 0;
    int[] res = new int[intervals.length];
    for (int i = 0; i < endIntervals.length; i++) {
      while (j < intervals.length && intervals[j][0] < endIntervals[i][1]) {
        j++;
      }
      res[hash.get(endIntervals[i])] = j == intervals.length ? -1 : hash.get(intervals[j]);
    }
    return res;
  }
}