 the unary numeral system is the bijective base-1 numeral system. it is the simplest numeral system to represent natural numbers: in order to represent a number n, an arbitrarily chosen symbol representing 1 is repeated n times. this system is used in tallying. for example, using the tally mark &#124;, the number 6 is represented as &#124;&#124;&#124;&#124;&#124;&#124;. in east asian cultures, the number three is represented as âä¸â, a character that is drawn with three strokes.. ==operations== addition and subtraction are particularly simple in the unary system, as they involve little more than string concatenation.. see in particular p.&nbsp; 48. the hamming weight or population count operation that counts the number of nonzero bits in a sequence of binary values may also be interpreted as a conversion from unary to binary numbers.. multiplication and division are more cumbersome, however. ==complexity== compared to standard positional numeral systems, the unary system is inconvenient and is not used in practice for large calculations. it occurs in some decision problem descriptions in theoretical computer science (e.g. some p-complete problems), where it is used to "artificially" decrease the run-time or space requirements of a problem. for instance, the problem of integer factorization is suspected to require more than a polynomial function of the length of the input as run-time if the input is given in binary, but it only needs linear runtime if the input is presented in unary.{{citation | last = feigenbaum | first = joan | autho
1_(number) Elementary_mathematics Numeral_systems