Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
Expand Up @@ -80,7 +80,32 @@ tags:
#### Python3

```python

class Solution:
def waysToBuildRooms(self, prevRoom: List[int]) -> int:
modulo = 10**9 + 7
ingoing = defaultdict(set)
outgoing = defaultdict(set)

for i in range(1, len(prevRoom)):
ingoing[i].add(prevRoom[i])
outgoing[prevRoom[i]].add(i)
ans = [1]

def recurse(i):
if len(outgoing[i]) == 0:
return 1

nodes_in_tree = 0
for v in outgoing[i]:
cn = recurse(v)
if nodes_in_tree != 0:
ans[0] *= comb(nodes_in_tree + cn, cn)
ans[0] %= modulo
nodes_in_tree += cn
return nodes_in_tree + 1

recurse(0)
return ans[0] % modulo
```

#### Java
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -104,7 +104,32 @@ tags:
#### Python3

```python

class Solution:
def waysToBuildRooms(self, prevRoom: List[int]) -> int:
modulo = 10**9 + 7
ingoing = defaultdict(set)
outgoing = defaultdict(set)

for i in range(1, len(prevRoom)):
ingoing[i].add(prevRoom[i])
outgoing[prevRoom[i]].add(i)
ans = [1]

def recurse(i):
if len(outgoing[i]) == 0:
return 1

nodes_in_tree = 0
for v in outgoing[i]:
cn = recurse(v)
if nodes_in_tree != 0:
ans[0] *= comb(nodes_in_tree + cn, cn)
ans[0] %= modulo
nodes_in_tree += cn
return nodes_in_tree + 1

recurse(0)
return ans[0] % modulo
```

#### Java
Expand Down
Original file line number Diff line number Diff line change
@@ -0,0 +1,26 @@
class Solution:
def waysToBuildRooms(self, prevRoom: List[int]) -> int:
modulo = 10**9 + 7
ingoing = defaultdict(set)
outgoing = defaultdict(set)

for i in range(1, len(prevRoom)):
ingoing[i].add(prevRoom[i])
outgoing[prevRoom[i]].add(i)
ans = [1]

def recurse(i):
if len(outgoing[i]) == 0:
return 1

nodes_in_tree = 0
for v in outgoing[i]:
cn = recurse(v)
if nodes_in_tree != 0:
ans[0] *= comb(nodes_in_tree + cn, cn)
ans[0] %= modulo
nodes_in_tree += cn
return nodes_in_tree + 1

recurse(0)
return ans[0] % modulo