Added doctest and more explanation about Dijkstra execution. (#1014)

* Added doctest and more explanation about Dijkstra execution.

* tests were not passing with python2 due to missing __init__.py file at number_theory folder

* Removed the dot at the beginning of the imported modules names because 'python3 -m doctest -v data_structures/hashing/*.py' and 'python3 -m doctest -v data_structures/stacks/*.py' were failing not finding hash_table.py and stack.py modules.

* Moved global code to main scope and added doctest for project euler problems 1 to 14.

* Added test case for negative input.

* Changed N variable to do not use end of line scape because in case there is a space after it the script will break making it much more error prone.

* Added problems description and doctests to the ones that were missing. Limited line length to 79 and executed python black over all scripts.

* Changed the way files are loaded to support pytest call.

* Added __init__.py to problems to make them modules and allow pytest execution.

* Added project_euler folder to test units execution

* Changed 'os.path.split(os.path.realpath(__file__))' to 'os.path.dirname()'

project_euler/problem_234/sol1.py

@@ -1,4 +1,22 @@
-# https://projecteuler.net/problem=234
+"""
+https://projecteuler.net/problem=234
+
+For an integer n ≥ 4, we define the lower prime square root of n, denoted by
+lps(n), as the largest prime ≤ √n and the upper prime square root of n, ups(n),
+as the smallest prime ≥ √n.
+
+So, for example, lps(4) = 2 = ups(4), lps(1000) = 31, ups(1000) = 37. Let us
+call an integer n ≥ 4 semidivisible, if one of lps(n) and ups(n) divides n,
+but not both.
+
+The sum of the semidivisible numbers not exceeding 15 is 30, the numbers are 8,
+10 and 12. 15 is not semidivisible because it is a multiple of both lps(15) = 3
+and ups(15) = 5. As a further example, the sum of the 92 semidivisible numbers
+up to 1000 is 34825.
+
+What is the sum of all semidivisible numbers not exceeding 999966663333 ?
+"""
+
 def fib(a, b, n):
     
     if n==1:
@@ -17,16 +35,22 @@ def fib(a, b, n):
     return c
 
 
-q=int(input())
-for x in range(q):
-    l=[i for i in input().split()]
-    c1=0
-    c2=1
-    while(1):
-        
-        if len(fib(l[0],l[1],c2))<int(l[2]):
-            c2+=1
-        else:
-            break
-    print(fib(l[0],l[1],c2+1)[int(l[2])-1])
- 
+def solution(n):
+    """Returns the sum of all semidivisible numbers not exceeding n."""
+    semidivisible = []
+    for x in range(n):
+        l=[i for i in input().split()]
+        c1=0
+        c2=1
+        while(1):
+            if len(fib(l[0],l[1],c2))<int(l[2]):
+                c2+=1
+            else:
+                break
+        semidivisible.append(fib(l[0],l[1],c2+1)[int(l[2])-1])
+    return semidivisible
+
+
+if __name__ == "__main__":
+    for i in solution(int(str(input()).strip())):
+        print(i)