v0.40: Create exercises. Challenge the community.

queen_boards

Your mission

Write a program that lists every valid placement for the N queens puzzle.

See it in action

./queen_boards 4 | cat -e

Expected result

1 3 0 2$
2 0 3 1$

Your checklist

For your own tracking. Tests grade your code.

The program expects exactly one argument (argc must be 2): a non-negative board size n.
Place exactly one queen in each column.
A solution line contains the row index for each column, from column 0 to column n - 1.
Rows are zero-based and values are separated by one space.
For n = 0, print one empty solution line.
Print solutions in the order produced by trying rows from 0 to n - 1 in each column.
If there is no solution, print nothing.
Return 1 when the argument count is wrong.

More examples

./queen_boards 2 | cat -e

Expected result

(empty result)

Constraints

Expected files

queen_boards.c

Allowed functions

atoiwritefprintfmalloccallocreallocfree

queen_boards

Recursion

Your mission

Write a program that lists every valid placement for the N queens puzzle.

See it in action

./queen_boards 4 | cat -e

Expected result

1 3 0 2$
2 0 3 1$

Your checklist

For your own tracking. Tests grade your code.

The program expects exactly one argument (argc must be 2): a non-negative board size n.
Place exactly one queen in each column.
A solution line contains the row index for each column, from column 0 to column n - 1.
Rows are zero-based and values are separated by one space.
For n = 0, print one empty solution line.
Print solutions in the order produced by trying rows from 0 to n - 1 in each column.
If there is no solution, print nothing.
Return 1 when the argument count is wrong.

More examples

./queen_boards 2 | cat -e

Expected result

(empty result)

Constraints

Expected files

queen_boards.c

Allowed functions

atoiwritefprintfmalloccallocreallocfree

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01Zero by zero boardWaiting

02One by one boardWaiting

03No solution for twoWaiting

04No solution for threeWaiting

05Five by five boardWaiting

06Missing sizeWaiting

07Four by four boardWaiting

queen_boards

Your mission

Write a program that lists every valid placement for the N queens puzzle.

See it in action

./queen_boards 4 | cat -e

Expected result

1 3 0 2$
2 0 3 1$

Your checklist

For your own tracking. Tests grade your code.

The program expects exactly one argument (argc must be 2): a non-negative board size n.
Place exactly one queen in each column.
A solution line contains the row index for each column, from column 0 to column n - 1.
Rows are zero-based and values are separated by one space.
For n = 0, print one empty solution line.
Print solutions in the order produced by trying rows from 0 to n - 1 in each column.
If there is no solution, print nothing.
Return 1 when the argument count is wrong.

More examples

./queen_boards 2 | cat -e

Expected result

(empty result)

Constraints

Expected files

queen_boards.c

Allowed functions

atoiwritefprintfmalloccallocreallocfree

v0.40: Create exercises. Challenge the community.

Meet Studio →

queen_boards

Recursion

Your mission

Write a program that lists every valid placement for the N queens puzzle.

See it in action

./queen_boards 4 | cat -e

Expected result

1 3 0 2$
2 0 3 1$

Your checklist

For your own tracking. Tests grade your code.

The program expects exactly one argument (argc must be 2): a non-negative board size n.
Place exactly one queen in each column.
A solution line contains the row index for each column, from column 0 to column n - 1.
Rows are zero-based and values are separated by one space.
For n = 0, print one empty solution line.
Print solutions in the order produced by trying rows from 0 to n - 1 in each column.
If there is no solution, print nothing.
Return 1 when the argument count is wrong.

More examples

./queen_boards 2 | cat -e

Expected result

(empty result)

Constraints

Expected files

queen_boards.c

Allowed functions

atoiwritefprintfmalloccallocreallocfree

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01Zero by zero boardWaiting

02One by one boardWaiting

03No solution for twoWaiting

04No solution for threeWaiting

05Five by five boardWaiting

06Missing sizeWaiting

07Four by four boardWaiting