Exercise "input/output"

1. Build a program that reads a set of numbers from the command-line and prints these numbers together with their sines and cosines (in a table form) to the standard output. Something like

   ./read-cmdline 1 2 3 4 5 > out.txt
   

   or

   ./read-cmdline $(cat input.txt) > out.txt
   

2. Build a program that reads a set of numbers from the standard input and prints these numbers together with their sines and cosines (in a table form) to the standard output. Something like

   echo 1 2 3 4 5 | ./read-stdin > out.txt
   

   or

   ./read-stdin < input.txt > out.txt
   cat input.txt | ./read-stdin > out.txt
   

3. Build a program that reads a set of numbers (separated by newlines) from "inputfile" and writes them together with their cosines (in a table form) to "outputfile". The program must read the names of the "inputfile" and "outputfile" from the command-line and the fopen them. Something like

   ./read-file input.txt out.txt