问两个函数之间所经过的时间怎么计算？

Stopwatch sw = new Stopwatch();
sw.Start();
Console.WriteLine(sample.palindrome()); // algorithm 1
sw.Stop();
Console.WriteLine(sw.ElapsedMilliseconds);//tried sw.elapsed and sw.elapsedticks
sw.Reset(); //tried with and without reset
sw.Start();
Console.WriteLine(sample.isPalindrome()); //algorithm 2
sw.Stop();
Console.WriteLine(sw.ElapsedMilliseconds);