https://dotnet.microsoft.com/download/dotnet-core/3.1 上哪个是编译cs的?

运行时间比较长，csc 有类似c++ -O3的选项吗？ c:\Windows\Microsoft.NET\Framework\v4.0.30319>timer E708 Timer 9.01 : Igor Pavlov : Public domain : 2009-05-31 S(100,000,000,000,000) 28,---,---,---,---,109 Kernel Time = 1.388 = 0% User Time = 1024.474 = 99% Process Time = 1025.862 = 99% Global Time = 1031.804 = 100%

m2对了

奇怪,你的代码编译有问题,把 int c = a[p - 1], m = (int)Math.Min(z, n / q); 改为 int c = a[p - 1]; m = (int)Math.Min(z, n / q);后 c:\Windows\Microsoft.NET\Framework\v4.0.30319>timer E708 Timer 9.01 : Igor Pavlov : Public domain : 2009-05-31 S(100,000,000) 7,421,539,985 Kernel Time = 0.015 = 14% User Time = 0.046 = 43% Process Time = 0.062 = 57% Global Time = 0.107 = 100%

其实有这个关系f(a*b)=f(a)*f(b),比如f(90)=f(9)*f(10)=4*4=16,利用这个关系就可以把更大的f(合数)算出来，质数不需要算，f(n)恒等于2