# Play safe
free @all
# Print Fibonacci numbers
cmode
	proc fib(x) {  # This x is a prototype
		# a, b, c will all be defined as global variables
    	a = 0 
    	b = 1 
    	while (b < x) { 
			print b, "\n"
        	c = b 
        	b += a 
        	a = c 
    	} 
	} 
	
	proc fib2(x) {
		auto a,b,c  # These a,b,c are local and hide global a,b,c above

		for(a=0,b=1;b<x;c=b,b+=a,a=c) {
			b    # This is equivalent to (print b, "\n")
		}
	}
	
	i=1
	while (i++<10) {
		fib(1000)
	}
	i=1
	while (i++<10) {
		fib2(1000)
	}
fmode