Ruby's "syntax error, unexpected `end', expecting end-of-input"

I have an exercise of accumulating proc parameters, but the "syntax error, unexpected `end’, expecting end-of-input" message appears during the actual manipulation, I can’t find where there is an extra or a missing "end", please tell me, thank you.

def total2(from, to, &block)    
    result = 0 
    from.upto(to) |num|         
        if block                
            result +=           
                block.call(num) 
        else                    
            result += num       
        end
    end
    return result               
end

p total2(1, 10)                 
p total2(1, 10){|num| num ** 2} 

>Solution :

do is missed

from.upto(to) do |num|
  # block body
end

https://ruby-doc.org/core/doc/syntax/calling_methods_rdoc.html#label-Block+Argument

The block argument is always last when sending a message to a method. A block is sent to a method using do … end or { … }