using System;

public class C
{
    public void M(int a, int b)
    {
        var s = "hello world";
        var sub1 = s[1..a];
        var sub2 = s[..2];
        var sub3 = s[3..];
        var sub4 = s[..^4];
        var sub5 = s[a..^b];
        var sub6 = s[..];

        Range range = 1..a;
        var sub7 = s[range];

        Span<int> sp = null;
        var slice1 = sp[5..a];
        var slice2 = sp[..6];
        var slice3 = sp[7..];
        var slice4 = sp[..^8];
        var slice5 = sp[a..^b];
        var slice6 = sp[..];

        Range range2 = 1..a;
        var slice7 = sp[range2];
    }
}