Number of Segments in a String – Leetcode #434

Problem Statement

This problem is from Leetcode – Number of Segments in a String. The problem statement is given below:

Given a string s, return the number of segments in the string. A segment is defined to be a contiguous sequence of non-space characters.

Solution

Approach – 1

We can simply use a StringTokenizer to solve this problem. See the code sample below:

public int countSegments(String s) {
		
		// return 0 if empty string
		 if(s.equals("")) {
			 return 0;
		 }
		 
		 StringTokenizer st = new StringTokenizer(s);
		 return st.countTokens();
	}

You can checkout the code from Github here: Number of Segments in String – First Approach. See the performance of this approach below:

Approach – 2

We may also use good old fashioned String split() and count the non-empty blocks. See the code sample below:

public int countSegments(String s) {

		// return if string is empty
		if(s.equals("")) {
			return 0;
		}

		// initialize counter to zero - this will count no. of segments
		int count = 0;

		// split on " "
		String[] splitarray = s.split(" ");
		
		// in a loop count non-empty segments
		for(int i=0; i<splitarray.length; i++) {

			if(!splitarray[i].equals("")) {
				count++;
			}
		}

		return count;

	}

You can checkout the code from Github here: Number of Segments in String – Second Approach. See the performance of this approach below: