Lessons from interviewing

As part of my job, I perform technical phone interviews (“phone screens”) for our group and a couple others. The basic phone screen is more about breadth then depth, touching on C, Unix, object-oriented programming and some data structures and algorithms over 30 to 45 minutes.

During this process, I’ve learned a few things, including:

  • Undergraduate computer science students at Brown prove P=NP as part of an assignment.
  • Half of 216 is 28 … or maybe 24. Not sure.
  • Dereferencing a pointer sets it to null, leaking memory.
  • Basic data types in ANSI C include array and string.

Kelley Blue Book used car pricing

When you use the Kelley Blue Book to price your used car, you go through a series of steps: Year, Make, Model, Value Type (Trade-In, Private Party, Retail), Trim and Condition.

It’s pretty straightfoward, but there’s one usability blunder that bugged me:

Kelley Blue Book trim selection

This screen is a waste.

If there’s only one possible trim, well, just select it for me automatically and save a step. Thanks.

Carbon dioxide worst in 800,000 years

Researchers in Antarctica have analyzed ice cores going back 800,000 years, 150,000 years further than before.

The news isn’t good:

“Ice cores reveal the Earth’s natural climate rhythm over the last 800,000 years. When carbon dioxide changed there was always an accompanying climate change. Over the last 200 years human activity has increased carbon dioxide to well outside the natural range,” explained Dr Wolff.

The “scary thing”, he added, was the rate of change now occurring in CO2 concentrations. In the core, the fastest increase seen was of the order of 30 parts per million (ppm) by volume over a period of roughly 1,000 years.

“The last 30 ppm of increase has occurred in just 17 years. We really are in the situation where we don’t have an analogue in our records,” he said.

Hertz discount codes

Here are a few Hertz discount codes I have lying around. Most of them aren’t really that special, but I figured writing them down here will benefit someone, and I won’t have to keep a few scraps of paper lying around.

CDP numbers:

  • Wells Fargo Card Services, Inc. CDP 65331
  • USA Hockey CDP 8972
  • CAA South Central Ontario CDP 279
  • Six Continents Hotesl Priority Club CDP 22754
  • Southwest Airlines Rapid Rewards CDP 205418
  • Air Canada
    • Aeroplan 221417
    • Prestige 436521
    • Elite 436520
    • Super Elite 118948

Coupons

  • $25 off a rental (expires 31-Dec-2007) PC 185301
  • $20 off “Leisure Weekend Rental” PC 945781
  • $25 off a weekly rental PC 945630
  • One car-class upgrade PC 945615
  • Free child seat (three-day minimum) PC 945626

These coupons are expired but may be worth trying:

  • One car-class upgrade (US PC 164290, Canada PC 164301, Puerto Rico PC 164312); use with CAA CDP
  • $20 off a weekend rental PC 169540; use with Wells Fargo CDP
  • $15 off a weekly or weekend rental PC 169536; use with Wells Fargo CDP

I’m not sure of the status of these (2007-08-14):

  • $15 off weekend PC 965624 or PC 999036 (CDP 282)
  • $20 off weekly PC 965506 or PC999014
  • Two free days PC983441 (CDP 205521)