using System;
using System.Text.RegularExpressions;
 
 
    static void Main()
    {
        Regex r = new Regex(@"\b\d{2}\.\d{2}\.\d{2}\b");
        string text1 = "Дата: 12.05.23";
        string text2 = "Нет даты";
        string text3 = "Дата рождения: 01.01.99";
        string text4 = "Некорректная дата: 32.13.22"; // Пример некорректной даты
 
        Console.WriteLine(r.IsMatch(text1)); // true
        Console.WriteLine(r.IsMatch(text2)); // false
        Console.WriteLine(r.IsMatch(text3)); // true
        Console.WriteLine(r.IsMatch(text4)); // false
    }
 

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