c# Random gives the same number [duplicate]

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• Random number generator only generating one random number 8 answers

My program generates a random integer between 0 and 1000 using System.Random at second once. The problem is, because it generates in the same millisecond time, the value always the same. How can I get a random number if the milliseconds are the same? I tried using some seeds like Math.sqrt(DateTimeOffset.Now.ToUnixTimeMilliseconds()) but there is a way what more fancy and doesn't consuming that much CPU like sqrt method?

Here's the code:

int x = new Random(0).Next((int)(radius + 0.5), (int)(Program.width - radius * 2 - 0.5));
int y = new Random(1).Next((int)(radius + 0.5), (int)(Program.height - radius * 2 - 0.5));