Nested Loop / Loop Tutorial

Question

I am looking for a good tutorial on writing and constructing loops. I understand the basics of loops, but nested loops give me a ton of problems. To give you an idea, the following figure below was difficult for me to understand.

1
12
123
1234
12345
123456

Answer 1

Loops

A cycle is a design that allows you to execute several commands several times. There are several circuit designs:

zero or more

These loops have a check at the start of the iteration and as such will be executed 0 or more times. An example of a while loop.

one or more

. do while while.

, . (, ).

.

. , , , .

, . . :

1
12
123
1234
12345
123456

, .

• 1
• 1 2
• 1 3
• ...

: n- 1 n.

, . .

• n = 1
• n = 2
• n = 3
• ...

Hm, n :

for n = 1 to 6
  s = ''
  for i = 1 to n // use the loopcounter of the outer loop
    s = s + char(i)
  end for
  out s
end for

Answer 2

:

• http://mathbits.com/mathbits/compsci/looping/nested.htm
• http://tldp.org/LDP/abs/html/nestedloops.html
• http://www.actionscript.org/resources/articles/5/1/The-power-of-nested-loops/Page1.html

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Answer 3

:

YouTube " SQL, , 6 ", http://www.youtube.com/watch?v=SmDZaH855qE

Answer 4

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Answer 5

- , Google. , , , , , , . , . /, , . , !

Answer 6

MIT Course. Safari, .

MIT python.

I found that working on this on paper, listing variables helps in learning how this works.

Answer 7

declare
s varchar2(10);
begin
  for n in 1..5 loop
    s:='';
    for i in 1..n loop
      s:=s||(i);
    end loop;
    dbms_output.put_line(s);
  end loop;
end;