R-PiaNer (pronounced "are piano" but with a weird accent for the last syllable) is a daily arithmetic game in which you try to make five targets with different combinations of six given input numbers. Numbers are placed on top of a "stack" in the middle of the page each time a number button is clicked. Clicking an operation button replaces the top two numbers on the stack with that result.
Hit a target by having it be the only number remaining on the stack. Press the AC button to start over with an empty stack. The ↶ button undoes one action.
R-PiaNer doesn't deal in negative numbers or fractions: the and buttons always use the bigger number first, and if a division won't come out evenly the button won't do anything. To hit a target you must hit it exactly; however, getting within 2 will mark you as "close" to the target.
Results can be shared once you've gotten something for at least three of the targets. Extra bragging rights are granted for hitting a target (or getting close) while using at least five (or better, all six) of the input numbers.
Every day is a different puzzle! Puzzles change at midnight, New York time.