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The Lumenary
Darasa la 3–5ComputationImepangwa

Repetition and decisions

Repeating steps with loops, making decisions with if–then rules, and algorithms for arithmetic such as column addition, in unplugged activities and simple block-based programs.

math.comp.loops-and-conditions

Somo la mada hii bado halijaandikwa. Muhtasari ulio hapa chini ni sehemu ya ramani ya mtaala na haujakaguliwa.

Inajengwa juu ya

Masharti ya awali ya lazima 1 (hadi chini kabisa)

Utajifunza

  • Use a loop to shorten a sequence of repeated instructions, such as drawing a square.
  • Write if–then rules for sorting objects or playing a simple game.
  • Explain the written algorithm for column addition as a loop over place values with a carry.

Fasili

  • A loop repeats a block of instructions a fixed number of times or until a condition holds.
  • A condition is a statement that is true or false, used to decide which instructions to follow.

Nadharia

  • 'Repeat 4 times: move forward, turn right 90°' draws a square.
  • Column addition works through the digits from right to left, carrying 1 whenever a column sum is 10 or more.

Mawazo potofu ya kawaida

  • Thinking a loop must run forever or exactly once.
  • Writing a stopping condition that can never become true, so that the loop never stops.

Inaelekea kwa

Ugunduzi wa hiari

  • Computability Can we always tell whether a program will stop? No algorithm can decide this for every program: the halting problem is undecidable.

Usomaji zaidi

  • Tim Bell, Ian H. Witten and Mike Fellows, Computer Science Unplugged