resource s1()
	op p() returns char x[1:20]
	proc p() returns x  {
		for [ i = lb(x) to ub(x) ] { x[i] = 'Z' }
		x[1:17] = chars("--mellow yellow--")
	}

	char  y[1:30] 
	y[1:26] = chars("abcdefghijklmnopqrstuvwxyz")
	y[27:30] = chars("1234")
	write(y)
	y[1:20] = p()
	write(y)
	y[1:26] = chars("abcdefghijklmnopqrstuvwxyz")
	y[27:30] = chars("1234")
	write(y)
	y[3:22] = p()
	write(y)

end