Grammage are the same weight paper having different cut size. However, a sheet of common copy paper that has a basis weight of does not have the same mass as the same size sheet of coarse paper (newsprint). In the former case, the standard ream is 500 sheets of paper, and in the latter, 500 sheets of paper. Here are some basic ream sizes for various types of paper. Units are inches except where noted. Sheets can be cut into four sheets, a standard for business stationery known conventionally as "letter sized paper". So, the ream became commonly used. The book-paper
Many-one reduction problem is easy to solve. The many-one reduction is more effective at separating problems into distinct complexity classes. However, the increased restrictions on many-one reductions make them more difficult to find. Many-one reductions were first used by Emil Post in a paper published in 1944. Later Norman Shapiro used the same concept in 1956 under the name "strong reducibility". Suppose "A" and "B" are formal languages over the alphabets Σ and Γ, respectively. A many-one reduction from "A" to "B" is a total computable function "f" : Σ → Γ that has the property that each word "w" is in