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CSharp · Console

/Program.cs

using System;

public class Program
{
	public static  void Main()
	{
		var str = "CamelCase";
		
		Console.WriteLine(GetLastPart(str));
	}
	
	private static Boolean IsUpperCased(char sym) {
		return sym >= 'A' && sym <= 'Z';
	}
	
	private static String GetLastPart(string camelCase) {
		var lastSymIndex = 0;
		
		for (int i = camelCase.Length - 1; i > 0 ; --i) {
			if (IsUpperCased(camelCase[i])) {
				lastSymIndex = i;
				break;
			}
		}
		return camelCase.Substring(lastSymIndex);
	}
	
}