apple-maps

Your mission

Find the first row of the map that is water all the way across.

today's brief

September 2012. Apple drops Google Maps from the iPhone and ships its own, and the screenshots start within hours: a farm outside Dublin labelled as an airport, bridges melting into the rivers they crossed. Tim Cook apologised in an open letter and pointed people at the competition. The ground underneath was wrong. Find the row the river runs through.

See it in action

river_row({0,0,1,1, 1,1,1,1, 1,1,0,0, 1,1,1,1}, 4, 4)

Expected result

Your checklist

For your own tracking. Tests grade your code.

map is a terrain grid stored one row after another and w cells wide, h rows tall, so the cell at row r and column c is map[r * w + c].
A cell holds 1 for water and 0 for ground. w is 1 or more.
Return the index of the first row whose cells are all water.
Return -1 when no row is water all the way across.

More examples

river_row({0,1,0, 1,0,1}, 3, 2)

Expected result

-1

river_row({1,1,1, 0,1,1}, 3, 2)

Expected result

Constraints

Expected files

terrain.c

Allowed functions

None. Write every helper yourself.

Back to compete

Solutions

apple-maps

Your mission

Find the first row of the map that is water all the way across.

today's brief

See it in action

river_row({0,0,1,1, 1,1,1,1, 1,1,0,0, 1,1,1,1}, 4, 4)

Expected result

Your checklist

For your own tracking. Tests grade your code.

map is a terrain grid stored one row after another and w cells wide, h rows tall, so the cell at row r and column c is map[r * w + c].
A cell holds 1 for water and 0 for ground. w is 1 or more.
Return the index of the first row whose cells are all water.
Return -1 when no row is water all the way across.

More examples

river_row({0,1,0, 1,0,1}, 3, 2)

Expected result

-1

river_row({1,1,1, 0,1,1}, 3, 2)

Expected result

Constraints

Expected files

terrain.c

Allowed functions

None. Write every helper yourself.

Back to compete

Solutions