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How to implement a binary tree?
...plementation of binary search tree.
#!/usr/bin/python
class Node:
def __init__(self, val):
self.l = None
self.r = None
self.v = val
class Tree:
def __init__(self):
self.root = None
def getRoot(self):
return self.root
def add(self, val):
...
How to serialize SqlAlchemy result to JSON?
...(json.JSONEncoder):
def default(self, obj):
if isinstance(obj.__class__, DeclarativeMeta):
# an SQLAlchemy class
fields = {}
for field in [x for x in dir(obj) if not x.startswith('_') and x != 'metadata']:
data = obj.__getattribute__(f...
Abstract methods in Python [duplicate]
...mething along these lines, using ABC
import abc
class Shape(object):
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def method_to_implement(self, input):
"""Method documentation"""
return
Also read this good tutorial: http://www.doughellmann.com/PyMOTW/abc/
You can...
What optimizations can GHC be expected to perform reliably?
...1.0-6e4c9bdc36eeb9121f27ccbbcb62e3f3
wired-in package rts mapped to builtin_rts
wired-in package template-haskell mapped to template-haskell-2.7.0.0-2bd128e15c2d50997ec26a1eaf8b23bf
wired-in package dph-seq not found.
wired-in package dph-par not found.
Hsc static flags: -static
*** Chasing dependen...
Append an object to a list in R in amortized constant time, O(1)?
... 2-element vector named c as is clearly intended!
– j_random_hacker
Dec 5 '11 at 16:45
7
So is th...
What is the canonical way to check for errors using the CUDA runtime API?
...on and wrapper macro like this:
#define gpuErrchk(ans) { gpuAssert((ans), __FILE__, __LINE__); }
inline void gpuAssert(cudaError_t code, const char *file, int line, bool abort=true)
{
if (code != cudaSuccess)
{
fprintf(stderr,"GPUassert: %s %s %d\n", cudaGetErrorString(code), file, lin...
Getting number of elements in an iterator in Python
...d work:
>>> iter = (i for i in range(50))
>>> sum(1 for _ in iter)
50
Although it does iterate through each item and count them, it is the fastest way to do so.
It also works for when the iterator has no item:
>>> sum(1 for _ in range(0))
0
Of course, it runs foreve...
How to automatically generate N “distinct” colors?
...uration [0, 100), lightness [0, 100)
for(i = 0; i < 360; i += 360 / num_colors) {
HSLColor c;
c.hue = i;
c.saturation = 90 + randf() * 10;
c.lightness = 50 + randf() * 10;
addColor(c);
}
share
...
How to check a string for specific characters?
...or ('D' in phrase):
return True
else:
return False
if __name__ == '__main__':
func1_time = timeit.timeit(func1, number=100000)
func2_time = timeit.timeit(func2, number=100000)
print('Func1 Time: {0}\nFunc2 Time: {1}'.format(func1_time, func2_time))
Output:
Func1 ...
capturing self strongly in this block is likely to lead to a retain cycle
...ng a weak reference to self before accessing timerDisp inside your block:
__weak typeof(self) weakSelf = self;
[player addPeriodicTimeObserverForInterval:CMTimeMakeWithSeconds(0.1, 100)
queue:nil
usingBlock:^(CMTime time) {
...