--- a/progs/collatz.scala Mon Nov 07 12:58:00 2016 +0000
+++ b/progs/collatz.scala Tue Nov 08 10:30:42 2016 +0000
@@ -1,29 +1,23 @@
-// Part 1
+// Part 1 about the 3n+1 conceture
+//=================================
-//(1)
-def collatz(n: Long): List[Long] =
- if (n == 1) List(1) else
- if (n % 2 == 0) (n::collatz(n / 2)) else
- (n::collatz(3 * n + 1))
+//(1) Complete the collatz function below. It should
+// recursively calculate the number of steps needed
+// until the collatz series reaches the number 1.
+// If needed you can use an auxilary function that
+// performs the recursion. The function should expect
+// arguments in the range of 1 to 10 Million.
-// an alternative that calculates the steps directly
-def collatz1(n: Long): Int =
- if (n == 1) 1 else
- if (n % 2 == 0) (1 + collatz1(n / 2)) else
- (1 + collatz1(3 * n + 1))
+def collatz(n: Long): Int = ...
-//(2)
-def collatz_max(bnd: Int): Int = {
- (for (i <- 1 to bnd) yield collatz(i).length).max
-}
+//(2) Complete the collatz bound function below. It should
+// calculuate how many steps are needed for each number
+// from 1 upto a bound and return the maximum number of
+// steps. You should expect bounds in the range of 1
+// upto 10 million.
+
+def collatz_max(bnd: Int): Int = ...
-val bnds = List(10, 100, 1000, 10000, 100000, 1000000, 10000000)
-
-for (bnd <- bnds) {
- val max = collatz_max(bnd)
- println(s"In the range of 1 - ${bnd} the maximum steps are ${max}")
-}
-
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/progs/collatz_.scala Tue Nov 08 10:30:42 2016 +0000
@@ -0,0 +1,29 @@
+// Part 1
+
+
+//(1)
+def collatz(n: Long): List[Long] =
+ if (n == 1) List(1) else
+ if (n % 2 == 0) (n::collatz(n / 2)) else
+ (n::collatz(3 * n + 1))
+
+// an alternative that calculates the steps directly
+def collatz1(n: Long): Int =
+ if (n == 1) 1 else
+ if (n % 2 == 0) (1 + collatz1(n / 2)) else
+ (1 + collatz1(3 * n + 1))
+
+
+//(2)
+def collatz_max(bnd: Int): Int = {
+ (for (i <- 1 to bnd) yield collatz(i).length).max
+}
+
+
+val bnds = List(10, 100, 1000, 10000, 100000, 1000000, 10000000)
+
+for (bnd <- bnds) {
+ val max = collatz_max(bnd)
+ println(s"In the range of 1 - ${bnd} the maximum steps are ${max}")
+}
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/progs/collatz_sol.scala Tue Nov 08 10:30:42 2016 +0000
@@ -0,0 +1,31 @@
+// Part 1 about the 3n+1 conceture
+//=================================
+
+
+//(1) Complete the collatz function below. It should
+//recursively calculates the number of steps needed
+//number until a series ends with 1
+
+def collatz(n: Long): List[Long] = ...
+
+
+// an alternative that calculates the steps directly
+def collatz1(n: Long): Int =
+ if (n == 1) 1 else
+ if (n % 2 == 0) (1 + collatz1(n / 2)) else
+ (1 + collatz1(3 * n + 1))
+
+
+//(2)
+def collatz_max(bnd: Int): Int = {
+ (for (i <- 1 to bnd) yield collatz(i).length).max
+}
+
+
+val bnds = List(10, 100, 1000, 10000, 100000, 1000000, 10000000)
+
+for (bnd <- bnds) {
+ val max = collatz_max(bnd)
+ println(s"In the range of 1 - ${bnd} the maximum steps are ${max}")
+}
+
--- a/progs/lecture1.scala Mon Nov 07 12:58:00 2016 +0000
+++ b/progs/lecture1.scala Tue Nov 08 10:30:42 2016 +0000
@@ -1,8 +1,4 @@
-// toList, toSet, toDouble
-// function definition
-// smart strings
-// maps
-// recursion
+
// webpages
@@ -27,6 +23,8 @@
//====================
println("test")
+
+
val tst = "This is a " + "test"
println(tst)
@@ -82,6 +80,9 @@
if (n == 0) 1 else n * fact(n - 1)
+
+
+
def fact2(n: BigInt): BigInt =
if (n == 0) 1 else n * fact2(n - 1)
@@ -93,6 +94,8 @@
//a recursive function
def gcd(x: Int, y: Int): Int = 2 //???
+//**String Interpolations**
+//=========================
//**Assert/Testing**