The number pair was invented by Descartes. Once, he was sick, lying in bed, and found a spider in the corner. Descartes begins with the position of the spider, and is marked as (0,0). Several pairs are used to represent all the intersections on the spider's web. Using several pairs of functions, we can easily point out the position of a certain point. I think number pairs can not only represent two-dimensional space (length and width), but also three-dimensional space (length, width and height) or four-dimensional space (length, width, height and time). All points in the world can be represented by number pairs, so number pairs will bring great convenience to our lives.

For the sake of convenience, before the invention of several pairs, we often express it like this: 5 ▲▲▲▲▲△☆ 4 □△∽◆ 3 ▲△●■℅ 2 ●●□▲※1∪∩〤● 0 65438. We say: ※▲※ on the right and ℅ below can be expressed in this way. After the invention of number pairs, it is much more convenient for us to express ourselves. For example, the above symbols can be represented as (5, 2) by a number pair. It should be noted that it should be determined according to the numbers on the coordinates. If the number on the coordinate changes, the expression will be different. ※ In this case: 1 ▲▲▲▲▲▲▲△☆ 2 □△∽◆ 3 ▲△●■℅ 4 ●●□▲※ 5 ∪∩〤● 012345 means (※ When playing gobang, we will find that the columns of gobang are represented by numbers and the rows are represented by letters. O ○○○○○○○○○○○○○○○○○○○○○○○○○○○○○9