langs a-z

Task/Factorial/UNIX-Shell/factorial-1.sh

@@ -0,0 +1,7 @@
+factorial() {
+  set -- "$1" 1
+  until test "$1" -lt 2; do
+    set -- "`expr "$1" - 1`" "`expr "$2" \* "$1"`"
+  done
+  echo "$2"
+}

Task/Factorial/UNIX-Shell/factorial-2.sh

@@ -0,0 +1,7 @@
+function factorial {
+  typeset n=$1 f=1 i
+  for ((i=2; i < n; i++)); do
+    (( f *= i ))
+  done
+  echo $f
+}

Task/Factorial/UNIX-Shell/factorial-3.sh

@@ -0,0 +1,7 @@
+factorial ()
+{
+  if [ $1 -eq 0 ]
+    then echo 1
+    else echo $(($1 * $(factorial $(($1-1)) ) ))
+  fi
+}

Task/Factorial/UNIX-Shell/factorial-4.sh

@@ -0,0 +1,5 @@
+function factorial {
+  typeset n=$1
+  (( n < 2 )) && echo 1 && return
+  echo $(( n * $(factorial $((n-1))) ))
+}

Task/Factorial/UNIX-Shell/factorial-5.sh

@@ -0,0 +1,13 @@
+alias factorial eval \''set factorial_args=( \!*:q )	\\
+	@ factorial_n = $factorial_args[2]		\\
+	@ factorial_i = 1				\\
+	while ( $factorial_n >= 2 )			\\
+		@ factorial_i *= $factorial_n		\\
+		@ factorial_n -= 1			\\
+	end						\\
+	@ $factorial_args[1] = $factorial_i		\\
+'\'
+
+factorial f 12
+echo $f
+# => 479001600