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  1.     using System.Text.RegularExpressions;
  2.     using System;
  3.  
  4.     public class Test
  5.     {
  6.     public static void Main()
  7.     {
  8.     String s = "123dfdf";
  9.     if (!Regex.IsMatch(s, @"^[a-zA-Z_][a-zA-Z_\d]*$")) {
  10.     Console.WriteLine("Error! Wrong format.");
  11.     }
  12.     else {
  13.     Console.WriteLine("Correct format.");
  14.     }
  15.     }
  16.  
  17.     }
Success #stdin #stdout 0.06s 34080KB
comments (?)
stdin 
Standard input is empty
stdout 
Error! Wrong format.
https://ideone.com/g4Wion
language:
C# (gmcs 5.20.1)
created:
9 years ago
visibility:
public

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