two beta,one 6 kyu

Author: sdwh

[6 kyu]Run-length encoding.py

@@ -0,0 +1,20 @@
+def run_length_encoding(s):
+	if len(s) == 0:
+		return []
+	res = []
+	char = s[0]
+	count = 1
+	for c in s[1:]:
+		if char == c:
+			count += 1
+		else:
+			res.append([count,str(char)])
+			char = c
+			count = 1
+	res.append([count,str(char)])
+	return res
+
+
+
+print(run_length_encoding('hello world'))
+# [[1,'h'],[1,'e'],[2,'l'],

[beta]Josephus Survivor.py

@@ -0,0 +1,28 @@
+def josephus_survivor(n,k):
+    circle = [i for i in range(1,n+1)]
+    index = -1
+    while circle.count(0) != n-1:
+        steps = k
+        while steps > 0:
+            if index + 1 > n-1:
+                index = 0
+                steps -= 1
+            elif circle[index+1] == 0:
+                index += 1
+            else:
+                index += 1
+                steps -= 1
+        circle[index] = 0
+        print(circle,index)
+    for num in circle:
+        if num != 0:
+            return num
+print(josephus_survivor(14,2))
+
+#[1,2,3,4,5,6,7] - initial sequence 3
+#[1,2,4,5,6,7] => 3 is counted out 6
+#[1,2,4,5,7] => 6 is counted out 9 2
+#[1,4,5,7] => 2 is counted out 12 5
+#[1,4,5] => 7 is counted out 15 
+#[1,4] => 5 is counted out
+#[4] => 1 is the last element - the survivor!

[beta]Playing with digits.py

@@ -0,0 +1,5 @@
+def dig_pow(n, p):
+    total = sum([(int(d)**power) for power,d in enumerate([d for d in str(n)],p)])
+    return -1 if total%n != 0 else int(total/n)
+
+print(dig_pow(46288, 3))