_57.java

package com.fishercoder.solutions;

import com.fishercoder.common.classes.Interval;

import java.util.ArrayList;
import java.util.List;

public class _57 {

    public static class Solution1 {
        public List<Interval> insert(List<Interval> intervals, Interval newInterval) {
            List<Interval> result = new ArrayList<>();
            int i = 0;
            // add all the intervals ending before newInterval starts
            while (i < intervals.size() && intervals.get(i).end < newInterval.start) {
                result.add(intervals.get(i++));
            }
            // merge all overlapping intervals to one considering newInterval
            while (i < intervals.size() && intervals.get(i).start <= newInterval.end) {
                newInterval = new Interval( // we could mutate newInterval here also
                        Math.min(newInterval.start, intervals.get(i).start),
                        Math.max(newInterval.end, intervals.get(i).end));
                i++;
            }
            result.add(newInterval);
            // add all the rest
            while (i < intervals.size()) {
                result.add(intervals.get(i++));
            }
            return result;
        }
    }
}