Units of paper quantity Simon Winchester, in "The Surgeon of Crowthorne", cites a specific number, defining quire as "a booklet eight pages thick." Several European words for quire keep the meaning of "book of paper": Ger. "Buch von Papier", Dan. "bog papir", Du. "bock papier". In blankbook binding, "quire" is a term indicating 80 pages. A ream of paper is a quantity of sheets of the same size and quality. International standards organizations define the ream as 500 identical sheets. This ream of 500 sheets (20 quires of 25 sheets) is also known as a 'long' ream, and is gradually replacing the old value
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