wffurr

def isBalanced(root):
    """ returns true if the tree is balanced, i.e. the depths of the children vary by no more than one """
    heights = set()
    getHeights(root, 0, heights)
    return not heights or (max(heights) - min(heights) <= 1)

def getHeights(node, h, heights):
    """ add the height of this node's children to heights """
    if node is None:
        return

wffurr

public class DecimalToBinary {
    /** Given a decimal number as a string, returns the binary representation as a string or "ERROR" if it can't be converted to binary */
    public static String decimalToBinary(String decimal) {
        int dec = 0;
        try {
            dec = Integer.parseInt(decimal);
        } catch(NumberFormatException ex) {
            return "ERROR";
        }
        if(dec == 0) return "0";

wffurr

#include <stdlib.h>
#include <stdio.h>

/* sets bits i through j in tgt to match src */
void setBits(int *tgt, int src, short i, short j) {
    int mask = (((int)pow(2, j - i + 1)) - 1) << i;
    *tgt = (src & mask) | (*tgt & ~mask);
}

#include <math.h>

wffurr

/**
 * Combines two maps with the same key into a map of key to tuple(value 1, optional value 2)
 */
public static <K, V1, V2> Map<K, Tuple<V1, Optional<V2>>> 
    zip(Map<K, V1> map1, Map<K, V2> map2)
{
    Map<K, Tuple<V1, Optional<V2>>> results = new HashMap<>();
    for (K key : map1.keySet())
    {
        V1 val1 = map1.get(key);

wffurr

#include<stdio.h>
#include<limits.h>
#include<math.h>

/** returns the number of 1 bits in x */
short countBits(int x) {
    short count = 0;
    int mask = 1;
    for(short i = 0; i < sizeof(x); i++) {
        if((mask & x) == mask) {

wffurr

"""
Implement a queue with two stacks

Interview practice from coding for interviews - March 2014
"""

class Staqueue(object):
    """ Implements a queue with two stacks 

    One stack is used for enqueing, and the other dequeing.  If an enqueue is requested

wffurr

--------- beginning of /dev/log/system
I/LocationManagerService(  261): remove passive (pid 1430), next minTime = 0
I/LocationManagerService(  261): request passive (pid 1430) 0 0
I/LocationManagerService(  261): remove passive (pid 1430), next minTime = 0
I/LocationManagerService(  261): request passive (pid 1430) 0 0
I/LocationManagerService(  261): remove passive (pid 1430), next minTime = 0
I/LocationManagerService(  261): request passive (pid 1430) 0 0
I/LocationManagerService(  261): remove passive (pid 1430), next minTime = 0
I/LocationManagerService(  261): request passive (pid 1430) 0 0
I/LocationManagerService(  261): request passive (pid 14979) 0 0

wffurr

<6>[    0.000000] Initializing cgroup subsys cpu
<5>[    0.000000] Linux version 3.0.31+ (hashcode@hashcode-UB) (gcc version 4.4.3 (GCC) ) #2 SMP PREEMPT Mon Jul 2 00:43:34 PDT 2012
<4>[    0.000000] CPU: ARMv7 Processor [411fc093] revision 3 (ARMv7), cr=10c5387d
<4>[    0.000000] CPU: VIPT nonaliasing data cache, VIPT aliasing instruction cache
<4>[    0.000000] Machine: OMAP4430
<4>[    0.000000] Ignoring tag cmdline (using the default kernel command line)
<6>[    0.000000] Reserving 16777216 bytes SDRAM for VRAM
<4>[    0.000000] Memory policy: ECC disabled, Data cache writealloc
<6>[    0.000000] ***********************
<6>[    0.000000] OMAP4430 ES2.3 type(GP)