SubString using suffix array logic

Solution.java

/*********************************************
My TestCases:

2
aab
aac
3
3
7
23
----------
6
banana
anaconda
anamoly
band
blue
ugly
6
37
93
25
2
50
12
**********************************************/


package strings;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Map;
import java.util.Scanner;
import java.util.TreeMap;

public class Solution{

	
	public static void solution1() 
	{
		Scanner sc = new Scanner(System.in);
		int noOfStr = sc.nextInt();
                /** Create suffix map instead of suffix array **/
		Map<String,Integer> unionMap = new TreeMap<String, Integer>();
		String input = null;
		String subStr=null;
		for (int i = 0; i < noOfStr; i++) {
			input = sc.next();
			int len = input.length();

			for (int start = 0; start < len; start++){	
				subStr = input.substring(start);
				unionMap.put(subStr,subStr.length());	
			}
		}

                /** Sort the suffixes **/
		ArrayList<String> suffixArr = new ArrayList<String>(unionMap.keySet());
		Collections.sort(suffixArr);
		
		int sufArrSize = suffixArr.size();
		int substrSum[] = new int[sufArrSize];
		int overlap = 0;
		String s1=null,s2=null;
		substrSum[0] = suffixArr.get(0).length();
		int max = 0;
		
		for(int i=0; i<sufArrSize-1; i++){
			overlap=0;
			s1=suffixArr.get(i);
			s2=suffixArr.get(i+1);
			for(int j=0; j<suffixArr.get(i).length(); j++){
				if(s1.charAt(j)==s2.charAt(j)){
					overlap++;
				}
				else
					break;
			}
			max= substrSum[i+1]= substrSum[i] + (s2.length()-overlap);			
		}
		
		
		
		int noOfOutput = sc.nextInt();		
		
		/*for(int i=0; i<substrSum.length; i++)
			System.out.println(suffixArr.get(i)+"\t"+substrSum[i]);
		*/
		
		
		for (int i = 0; i < noOfOutput; i++) {
			int index = sc.nextInt();
			if (index > max){
				//System.out.println("index:"+index+",max:"+max);
				System.out.println("INVALID");
			}
			else{
				int ind = binSearch(substrSum, index, 0, sufArrSize-1);
				//System.out.println("index:"+index+",ind:"+ind+",val[ind]:"+substrSum[ind]);
				System.out.println(suffixArr.get(ind).substring(0, (suffixArr.get(ind).length()-(substrSum[ind] - index))));				
			}
		}
	}
	
	
	
	
	public static int binSearch(int[] in, int num, int low, int high){
				
		if(low>high)
			return ((low+high)/2)+1;
		if(low==high)
			return low;
		
		int mid = (low+high)/2;
		
		if(in[mid]==num)
			return mid;
		else if(num > in[mid])
			return binSearch(in, num, mid+1, high);
		else
			return binSearch(in, num, low, mid);
		
	}
	

	public static void main(String[] a) {
			Solution.solution1();
	}

}