2.11 Nested Iteration

1. Exam Points

• Nested iteration (while in while, for in for, while in for, for in while)
• Count the number of times a statement is executed.
• Note: Analyze nested loops
  • Analyze how the outer i changes
  • Analyze how the inner j changes with the outer i
  • Analyze what is printed or executed in the inner loop

• Note:
  • Pay attention how the loop control variables of the inner and outer loops changes. (++, --, +=2, -=2).
  • When printing multiple lines using nested loops:
    • the outer loop controls how many lines are printed,
    • the inner loop controls what is printed for each line.
    • Rule out wrong options first if possible.
    • What is printed in the loop (outer i or inner j)

2. Knowledge Points

(1) Nested Iteration

• Nested iteration statements are iteration statements that appear in the body of another iteration statement.
• Example 1:
  
  
  • Analyze nested loops
    • 1. Analyze how the outer i changes (1~6)
    • 2. Analyze how the inner j changes with the outer i (1~i)
    • 3. Analyze what is printed or executed in the inner loop (dog)
• Example 2:
  

3. Exercises

• Practice
• Solution