Nested Iteration - AP Computer Science A
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What is the time complexity of three nested loops, each iterating over $n$ elements?
What is the time complexity of three nested loops, each iterating over $n$ elements?
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$O(n^3)$. Three nested loops create cubic complexity: $n \times n \times n = n^3$.
$O(n^3)$. Three nested loops create cubic complexity: $n \times n \times n = n^3$.
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What is the result of these loops? for(int i=2; i>=0; i--) { for(int j=0; j<=i; j++) { System.out.print(j); } }
What is the result of these loops? for(int i=2; i>=0; i--) { for(int j=0; j<=i; j++) { System.out.print(j); } }
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- i decreases 2→0; j runs 0 to i, printing j values.
- i decreases 2→0; j runs 0 to i, printing j values.
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What is printed by this code? for(int i=1; i<=2; i++) { for(int j=1; j<=i; j++) { System.out.print(i); } }
What is printed by this code? for(int i=1; i<=2; i++) { for(int j=1; j<=i; j++) { System.out.print(i); } }
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- i=1→j=1 prints 1, i=2→j=1,2 prints 2,2.
- i=1→j=1 prints 1, i=2→j=1,2 prints 2,2.
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What is printed by this code? for(int i=0; i<3; i++) { for(int j=0; j<i; j++) { System.out.print(i+j); } }
What is printed by this code? for(int i=0; i<3; i++) { for(int j=0; j<i; j++) { System.out.print(i+j); } }
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- i=1→no output, i=2→j=0,1 giving 2+0=2, 2+1=3.
- i=1→no output, i=2→j=0,1 giving 2+0=2, 2+1=3.
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Identify the error in this nested loop: for(int i=0; i < 5; i++) { for(int j=0; j < 5; j++) }
Identify the error in this nested loop: for(int i=0; i < 5; i++) { for(int j=0; j < 5; j++) }
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Missing braces around inner loop body. Loop bodies require braces to contain multiple statements or nested loops.
Missing braces around inner loop body. Loop bodies require braces to contain multiple statements or nested loops.
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What is the time complexity of a nested loop with two loops iterating over $n$ elements each?
What is the time complexity of a nested loop with two loops iterating over $n$ elements each?
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$O(n^2)$. Each outer iteration runs inner loop $n$ times: $n \times n = n^2$.
$O(n^2)$. Each outer iteration runs inner loop $n$ times: $n \times n = n^2$.
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What is the output of this nested loop? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i+j); } }
What is the output of this nested loop? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i+j); } }
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- Outer loop: i=0,1; inner loop: j=0,1; outputs i+j for each combination.
- Outer loop: i=0,1; inner loop: j=0,1; outputs i+j for each combination.
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How many times does the inner loop execute? for(int i=0; i<3; i++) { for(int j=0; j<4; j++) { } }
How many times does the inner loop execute? for(int i=0; i<3; i++) { for(int j=0; j<4; j++) { } }
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12 times. Outer loop runs 3 times, inner loop runs 4 times each: $3 \times 4 = 12$.
12 times. Outer loop runs 3 times, inner loop runs 4 times each: $3 \times 4 = 12$.
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What is the purpose of nested iteration in array processing?
What is the purpose of nested iteration in array processing?
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To iterate over multi-dimensional arrays. Outer loop accesses rows, inner loop accesses columns of 2D arrays.
To iterate over multi-dimensional arrays. Outer loop accesses rows, inner loop accesses columns of 2D arrays.
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What is printed by this loop? for(int i=0; i<1; i++) { for(int j=0; j<3; j++) { System.out.print(j); } }
What is printed by this loop? for(int i=0; i<1; i++) { for(int j=0; j<3; j++) { System.out.print(j); } }
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- Outer loop runs once (i=0), inner loop prints j values 0, 1, 2.
- Outer loop runs once (i=0), inner loop prints j values 0, 1, 2.
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How can nested iteration be used to compare all pairs of elements in an array?
How can nested iteration be used to compare all pairs of elements in an array?
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Use two loops, each iterating over the array. Outer loop selects first element, inner loop compares with remaining elements.
Use two loops, each iterating over the array. Outer loop selects first element, inner loop compares with remaining elements.
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What is the result of these nested loops? for(int i=1; i<=2; i++) { for(int j=1; j<=2; j++) { System.out.print(i*j); } }
What is the result of these nested loops? for(int i=1; i<=2; i++) { for(int j=1; j<=2; j++) { System.out.print(i*j); } }
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- i=1,2; j=1,2; outputs products: 1×1=1, 1×2=2, 2×1=2, 2×2=4.
- i=1,2; j=1,2; outputs products: 1×1=1, 1×2=2, 2×1=2, 2×2=4.
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What is printed by the loop? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { if(j==1) break; System.out.print(j); } }
What is printed by the loop? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { if(j==1) break; System.out.print(j); } }
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- Break exits inner loop when j=1, so only j=0 prints each iteration.
- Break exits inner loop when j=1, so only j=0 prints each iteration.
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What is a common use case of nested loops in matrix operations?
What is a common use case of nested loops in matrix operations?
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Iterating over rows and columns. Outer loop for rows, inner loop for columns in matrix traversal.
Iterating over rows and columns. Outer loop for rows, inner loop for columns in matrix traversal.
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What is the function of the inner loop in this code? for(int i=0; i<3; i++) { for(int j=0; j<2; j++) { System.out.print("*"); } }
What is the function of the inner loop in this code? for(int i=0; i<3; i++) { for(int j=0; j<2; j++) { System.out.print("*"); } }
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Prints "**" for each iteration of the outer loop. Inner loop prints two stars for each of three outer iterations.
Prints "**" for each iteration of the outer loop. Inner loop prints two stars for each of three outer iterations.
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Identify the error: for(int i=0; i<2; i++) { for(int j=0; j<2; j++) System.out.print(i j); }
Identify the error: for(int i=0; i<2; i++) { for(int j=0; j<2; j++) System.out.print(i j); }
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Missing '+' between 'i' and 'j'. Concatenation operator missing between variables i and j.
Missing '+' between 'i' and 'j'. Concatenation operator missing between variables i and j.
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How is a nested loop structure typically used in a sorting algorithm?
How is a nested loop structure typically used in a sorting algorithm?
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To compare and swap elements. Outer loop selects elements, inner loop finds position or comparison.
To compare and swap elements. Outer loop selects elements, inner loop finds position or comparison.
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What is printed by this code? for(int i=1; i<=3; i++) { for(int j=1; j<=i; j++) { System.out.print(j); } }
What is printed by this code? for(int i=1; i<=3; i++) { for(int j=1; j<=i; j++) { System.out.print(j); } }
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- Inner loop runs from 1 to i: i=1→j=1, i=2→j=1,2, i=3→j=1,2,3.
- Inner loop runs from 1 to i: i=1→j=1, i=2→j=1,2, i=3→j=1,2,3.
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What is the purpose of the outer loop in a nested iteration?
What is the purpose of the outer loop in a nested iteration?
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Controls the number of times the inner loop executes. Outer loop determines how many times the inner loop executes completely.
Controls the number of times the inner loop executes. Outer loop determines how many times the inner loop executes completely.
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What does this loop print? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i*j); } }
What does this loop print? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i*j); } }
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- i=0,1; j=0,1; outputs i×j: 0×0=0, 0×1=0, 1×0=0, 1×1=1.
- i=0,1; j=0,1; outputs i×j: 0×0=0, 0×1=0, 1×0=0, 1×1=1.
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What is the output of this code? for(int i=2; i>=0; i--) { for(int j=0; j<=i; j++) { System.out.print(i); } }
What is the output of this code? for(int i=2; i>=0; i--) { for(int j=0; j<=i; j++) { System.out.print(i); } }
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- i decreases 2→0; j runs 0 to i, printing i value each time.
- i decreases 2→0; j runs 0 to i, printing i value each time.
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Identify the error: for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.println(i+j); }
Identify the error: for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.println(i+j); }
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Missing closing brace for loops. Nested loops need closing braces for both inner and outer structures.
Missing closing brace for loops. Nested loops need closing braces for both inner and outer structures.
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How can nested loops be used to calculate the sum of elements in a 2D array?
How can nested loops be used to calculate the sum of elements in a 2D array?
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Sum elements in inner loop, iterate rows in outer loop. Outer loop processes rows, inner loop sums elements within each row.
Sum elements in inner loop, iterate rows in outer loop. Outer loop processes rows, inner loop sums elements within each row.
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What will this code output? for(int i=0; i<2; i++) { for(int j=0; j<=i; j++) { System.out.print(j); } }
What will this code output? for(int i=0; i<2; i++) { for(int j=0; j<=i; j++) { System.out.print(j); } }
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- i=0→j=0, i=1→j=0,1; prints j values for each valid combination.
- i=0→j=0, i=1→j=0,1; prints j values for each valid combination.
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What does this code output? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i*j); } }
What does this code output? for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i*j); } }
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- i=0,1; j=0,1; outputs i×j: 0×0=0, 0×1=0, 1×0=0, 1×1=1.
- i=0,1; j=0,1; outputs i×j: 0×0=0, 0×1=0, 1×0=0, 1×1=1.
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What is printed by this loop? for(int i=0; i<1; i++) { for(int j=0; j<3; j++) { System.out.print("*"); } }
What is printed by this loop? for(int i=0; i<1; i++) { for(int j=0; j<3; j++) { System.out.print("*"); } }
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***. Outer loop runs once, inner loop prints three asterisks.
***. Outer loop runs once, inner loop prints three asterisks.
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What does the inner loop control in a nested loop?
What does the inner loop control in a nested loop?
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The repeated action for each outer loop iteration. Inner loop defines what happens for each outer loop iteration.
The repeated action for each outer loop iteration. Inner loop defines what happens for each outer loop iteration.
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Find the output: for(int i=0; i<3; i++) { for(int j=i; j<3; j++) { System.out.print("*"); } }
Find the output: for(int i=0; i<3; i++) { for(int j=i; j<3; j++) { System.out.print("*"); } }
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******. i=0→j runs 3 times, i=1→j runs 2 times, i=2→j runs 1 time.
******. i=0→j runs 3 times, i=1→j runs 2 times, i=2→j runs 1 time.
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What is printed by this code? for(int i=1; i<=3; i++) { for(int j=1; j<=i; j++) { System.out.print(j); } }
What is printed by this code? for(int i=1; i<=3; i++) { for(int j=1; j<=i; j++) { System.out.print(j); } }
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- Inner loop runs from 1 to i: i=1→j=1, i=2→j=1,2, i=3→j=1,2,3.
- Inner loop runs from 1 to i: i=1→j=1, i=2→j=1,2, i=3→j=1,2,3.
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Identify the error: for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i j); } }
Identify the error: for(int i=0; i<2; i++) { for(int j=0; j<2; j++) { System.out.print(i j); } }
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Missing '+' between 'i' and 'j'. Concatenation operator missing between variables i and j in print statement.
Missing '+' between 'i' and 'j'. Concatenation operator missing between variables i and j in print statement.
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