Number of Segments in a String

Count the number of segments in a string, where a segment is defined to be a contiguous sequence of non-space characters.

Please note that the string does not contain any non-printable characters.

Example:

Input: "Hello, my name is John"

Output: 5

Solution:

using System;
using System.Collections.Generic;
using System.Text;

namespace LeetCode.AskGif.Easy.String
{
 public class CountSegmentsSoln
 {
 public int CountSegments(string s)
 {
 if (s.Length == 0) return 0;
 var list = new List<string>();
 int count = 1;
 if(s[0] == ' ')
 {
 count = 0;
 }

 for(int i = 1; i < s.Length-1; i++)
 {
 if(s[i] == ' ' && s[i+1] != ' ')
 {
 list.Add(s.Substring(0, i));
 count++;
 }
 }

 return count;
 }
 }
}

Time Complexity: O(n)

Space Complexity: O(1)

Unit Tests:

using LeetCode.AskGif.Easy.String;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using System;
using System.Collections.Generic;
using System.Text;

namespace CodingUnitTest.Easy.String
{
 [TestClass]
 public class CountSegmentsSolnTests
 {
 [TestMethod]
 public void CountSegmentsSoln_First()
 {
 var s = "Hello, my name is John";
 var output = 5;
 var res = new CountSegmentsSoln().CountSegments(s);

 Assert.AreEqual(res, output);
 }

 [TestMethod]
 public void CountSegmentsSoln_Second()
 {
 var s = " ";
 var output = 0;
 var res = new CountSegmentsSoln().CountSegments(s);

 Assert.AreEqual(res, output);
 }

 [TestMethod]
 public void CountSegmentsSoln_Third()
 {
 var s = "Of all the gin joints in all the towns in all the world, ";
 var output = 13;
 var res = new CountSegmentsSoln().CountSegments(s);

 Assert.AreEqual(res, output);
 }
 }
}