Adding String-2

Author: Jem Chang

String-2/cat_dog.py

@@ -0,0 +1,15 @@
+"""
+Return True if the string "cat" and "dog" appear the same number of times in the given string.
+"""
+def cat_dog(x):
+  cat = 0
+  dog = 0
+  for i in range(len(x)-2):
+    if x[i:i+3] == 'cat':
+      cat = cat + 1
+    if x[i:i+3] == 'dog':
+      dog = dog + 1
+  if dog == cat:
+    return True
+  else:
+    return False

String-2/count_code.py

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+"""
+Return the number of times that the string "code" appears anywhere in the given string,
+except we'll accept any letter for the 'd', so "cope" and "cooe" count.
+"""
+def count_code(x):
+  count = 0
+  for i in range(len(x)-3):
+    if x[i:i+2] == 'co' and x[i+3:i+4] == 'e':
+      count = count + 1
+    else:
+      count = count
+  return count

String-2/count_hi.py

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+"""
+Return the number of times that the string "hi" appears anywhere in the given string.
+"""
+def count_hi(x):
+  count = 0
+  for i in range(len(x)-1):
+    if x[i:i+2] == 'hi':
+      count = count + 1
+    else:
+      count = count
+  return count

String-2/double_char.py

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+"""
+Given a string, return a string where for every char in the original, there are two chars.
+"""
+
+def double_char(x):
+  all = str()
+  for i in x:
+    all = all + i + i
+  return all

String-2/end_other.py

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+"""
+Given two strings, return True if either of the strings appears at the very end of the other string,
+ignoring upper/lower case differences (in other words, the computation should not be "case sensitive").
+Note: s.lower() returns the lowercase version of a string.
+"""
+def end_other(a, b):
+  alow = a.lower()
+  blow = b.lower()
+  if len(a) > len(b) and blow == alow[-(len(b)):]:
+    return True
+  if len(b) > len(a) and alow == blow[-(len(a)):]:
+    return True
+  if alow == blow:
+    return True
+  else:
+    return False

String-2/xyz_there.py

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+"""
+Return True if the given string contains an appearance of "xyz" where the xyz is not directly preceeded
+by a period (.). So "xxyz" counts but "x.xyz" does not.
+"""
+def xyz_there(x):
+  if x.count('xyz') == 0:
+    return False
+  elif x.count('.xyz') != 0:
+    y = x.replace('.xyz','')
+    if y.count('xyz') > 0:
+      return True
+    return False
+  else:
+    return True
+