Loops in Structured Programming

Types of Loops  

- Count‑controlled loop — FOR…NEXT 

- Pre‑condition loop — WHILE…ENDWHILE  

- Post‑condition loop — REPEAT…UNTIL  

FOR…NEXT Loop  

- Repetition is known.  

- Count‑controlled, fixed number of iterations.  

- No condition required.  

- Example:  

FOR Count = 1 TO 10

   // statements

ENDFOR

WHILE…ENDWHILE Loop  

- Repetition is unknown.  

- Conditional loop, checked before execution (pre‑condition).  

- Loop runs until the condition remains true.  

- Example:  

Count = 0

WHILE Count < 10 DO

   Count = Count + 1

ENDWHILE

REPEAT…UNTIL Loop  

- Repetition is unknown.  

- Conditional loop, checked after execution (post‑condition).  

- Loop runs until the condition becomes false.  

- Example:  

Count = 0

REPEAT

   Count = Count + 1

UNTIL Count = 10

Programming Techniques  

- SUM — Used to calculate the total of values.  

- COUNT — Used to calculate the number of items or iterations.