PayPal Credits Man With $92 Quadrillion

solareagle writes "Pennsylvania resident Chris Reynolds got quite a shock when he opened his most recent PayPal statement — it said he had a $92,233,720,368,547,800 balance in his account. 'I'm just feeling like a million bucks,' Reynolds told the [Philadelphia] Daily News yesterday. 'At first I thought that I owed quadrillions. It was quite a big surprise.' When asked what he would do with the money, he said, 'I would pay the national debt down first. Then I would buy the Phillies, if I could get a great price.' The Daily News speculates that the astronomical balance may be related to PayPal's new Galactic initiative, announced last month, to expand its business beyond Earth." He should have quickly minted a new coin.

Comments

Signed integer overflow

[GerbilSoft]

2^63 - 1 == 9,223,372,036,854,775,807

Assuming PayPal's currency values are stored in cents, dividing that by 100 results in $92,233,720,368,547,758.07. Looks like a 64-bit signed integer overflowed (or in this case, underflowed), resulting in integer wraparound.

Re:Signed integer overflow

[Omega Hacker]

Not sure you quite get the concept of underflow.... If it's a 64-bit field in cents and he had $1, an unsigned subtract of $2 would result in a balance of $92,233,720,368,547,757.08 (give or take a few cents).