## Monday, August 23, 2010

### Enter numbers the difference of numbers zero and twenty

"Enter numbers the difference of numbers 0 (zero) and 20 (twenty)" - a similar task very often meets in the Internet. Interesting that I do not know exactly, how her it is correct to decide. Omniscient Wikipedia reports bashfully, that a difference of numbers is a result of deduction of two numbers. But here, as correct to execute the action of deduction, this collection of wisdom holds back. In fact two variants of decision of this task are possible:

1. From the first number to subtract second 0 - 20 = - 20 (to take away zero twenty evened minus twenty)

2. From a greater number to subtract less 20 - 0 = 20 (twenty to take away zero evened twenty)

As see, we got two different answers. In one there is a sign minus, in other the sign minus it is not. Now we will begin to ratiocinate. A similar task is set by the program, the programs are written by programmers. I doubt that they remember about such nuances of school mathematics, as a sign is minus in the results of deduction of numbers. Therefore I suggest to operate by the tested method - by a scientific method. We will enter in a window numbers 20 (twenty) without a sign minus.

If Sim-Sim accepted our answer and opened access to treasures of the Internet, our experiment is completed. If a window answered us, that we are not right, then this iron will give out other pair of numbers to us.

Now we already the experienced users of this window. If it is again written us, for example, "Enter numbers the difference of numbers 0 (zero) and 16 (sixteen)", then we already know exactly, that it is needed in a window to enter - 16 (minus sixteen), with a mark minus ahead.

0 - 16 = -16

(zero minus sixteen evened minus sixteen)

If a window will write something type "Enter numbers the difference of numbers 1 (one) and 0 (zero)", then we without every vibrations enter a number 1 (one). In fact in this case and from the first number to take away second, and from a greater number to take away less, give an identical result is a positive number, without every signs minus.

1 - 0 = 1

(one minus zero evened one)

For all pair of numbers, if the first number anymore than second, a result will always be positive. For example:

20 - 14 = 6

(twenty minus fourteen evened six)

In a window it is needed to enter a number 6 (six, it a number is such).

In case if the program will take in head to flash the erudition and will give out to you a task "Enter numbers the difference of numbers 0 (zero) and 0 (zero)", not frightened and bravely enter a number 0 (zero)!

0 - 0 = 0

(zero minus zero evened zero)

Lighthouses for blondes. All, who searches answers for a question "That means enter the difference of numbers?" - you need to pass to this page!