\textit{"Why bother with subroutines when you can type fast?"} \textit{Vaughn Rokosz} In mathematics, the Fibonacci numbers are the numbers in the following sequence : \textbf{0}, \textbf{1}, \textbf{1}, \textbf{2}, \textbf{3}, \textbf{5}, \textbf{8}, \textbf{13}, \textbf{21}, \textbf{34}, … . By definition, the first two Fibonacci numbers are \textbf{0} and \textbf{1}, and each remaining number is the sum of the previous two. In mathematical terms, the sequence \textbf{F_n} of Fibonacci numbers is defined by the recurrence relation \textbf{F_\{n \}= F_\{n-1\}+F_\{n-2\}} with seed values \textbf{F_0} = \textbf{0} and \textbf{F_1} = \textbf{1}. Given the index of a Fibonacci number, \textbf{i}, you should write a program that calculates \textbf{F_i}. \InputFile The input file contains several lines. Each line contains an integer \textbf{i} (\textbf{0} ≤ \textbf{i} < \textbf{1000}) which indicates the index of a Fibonacci number. Input is terminated by End of File. \OutputFile For each line of input simply output \textbf{F_i}.