2. the term | refers to the 0 point (s) to the point instead of 2, which is equal to 2 | unit-2 at stage 0 means that vacancies to the point instead of-2, which is equal to 2 .
Like | 2 | means the distance from the point 0 to point 2, which is 2 units. | -2 | means the distance from point to point instead of 0 - 2, which is 2 units.
Such as | 2 | mean distance from point to point 0 instead of 2 which was 2 unit | - 2 | means the distance from point to point 0 instead of - 2 which was 2 unit .