Partition of label

class Solution { public List<Integer> partitionLabels(String s) { int intervals[][] = new int[26][2]; for(int i =0;i<intervals.length;i++){ intervals[i][0] = 501; intervals[i][1] = -1; } for(int i = 0;i<s.length();i++){ char c = s.charAt(i); int index = c-'a'; intervals[index][0] = Math.min(intervals[index][0],i); intervals[index][1] = Math.max(intervals[index][1],i); } //sorting  Arrays.sort(intervals,(a,b)-> a[0]-b[0]); //merging int start = intervals[0][0]; int end = intervals[0][1]; List<Integer> list = new ArrayList<>(); for(int i =1;i<intervals.length;i++){ if(intervals[i][0]==501) break;// exit as no need to traverse any further if(end >= intervals[i][0]){ start = Math.min(intervals[i][0],start); end = Math.max(intervals[i][1],end); } else{ list.add(end-start+1); // instead of keeping the range [start, end] in the list we are addting their sizes start = intervals[i][0]; end = intervals[i][1]; } } list.add(end-start+1); return list; } }