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What is the difference between dynamic and static polymorphism in Java?

...is a reference variable of type Class A pointing to object of class A. ‘a2’ is also reference variable of type class A but pointing to object of Class B. During compilation, while binding, compiler does not check the type of object to which a particular reference variable is pointing. It just ...
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How to print a linebreak in a python function?

... >>> A = ['a1', 'a2', 'a3'] >>> B = ['b1', 'b2', 'b3'] >>> for x in A: for i in B: print ">" + x + "\n" + i Outputs: >a1 b1 >a1 b2 >a1 b3 >a2 b1 >a2 b2 >a2 b3 >a3 b1 >a3 b2 ...
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Easy interview question got harder: given numbers 1..100, find the missing number(s) given exactly k

...,2,..,k. This reduces the problem to solving the system of equations a1 + a2 + ... + ak = b1 a12 + a22 + ... + ak2 = b2 ... a1k + a2k + ... + akk = bk Using Newton's identities, knowing bi allows to compute c1 = a1 + a2 + ... ak c2 = a1a2 + a1a3 + ... + ak-1ak ... ck = a1a2 ... ak If you e...
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How to sort a Ruby Hash by number value?

...ults, since it would not sort by string value... You should reverse a1 and a2 in your example Best way in any case (as per Mladen) is: metrics = {"sitea.com" => 745, "siteb.com" => 9, "sitec.com" => 10 } metrics.sort_by {|_key, value| value} # ==> [["siteb.com", 9], ["sitec.com", 10]...
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How to compare arrays in C#? [duplicate]

... compare two generic arrays: static bool ArraysEqual<T>(T[] a1, T[] a2) { if (ReferenceEquals(a1, a2)) return true; if (a1 == null || a2 == null) return false; if (a1.Length != a2.Length) return false; var comparer = EqualityComparer<T>.Default...
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How to compare arrays in JavaScript?

... same unsorted items (but not used multiple times), you can use a1.length==a2.length && a1.every((v,i)=>a2.includes(v)): var a1 =[1,2,3], a2 = [3,2,1]; (var a1 =[1,3,3], a2 = [1,1,3]; will not work as expected) – mems Nov 21 '16 at 15:25 ...
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Is iterating ConcurrentHashMap values thread safe?

...vate void run() { Accessor a1 = new Accessor(this.map); Accessor a2 = new Accessor(this.map); Mutator m = new Mutator(this.map); executor.execute(a1); executor.execute(m); executor.execute(a2); } } No exception will be thrown. Sharing the same iterator between accesso...
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How do I change the root directory of an apache server? [closed]

...oject. (see askubuntu.com/questions/337874/…) – sea26.2 Oct 4 '19 at 23:15  |  show 7 more comments ...
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CMake link to external library

...section \*\/#\/\* Begin PBXBuildFile section \*\/\ 26B12AA11C10544700A9A2BA \/\* GameKit.framework in Frameworks \*\/ = {isa = PBXBuildFile; fileRef = 26B12AA01C10544700A9A2BA \/\* GameKit.framework xxx\*\/; };#g s#\/\* Begin PBXFileReference section \*\/#\/\* Begin PBXFileReference section \*\...
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How to avoid reinstalling packages when building Docker image for Python projects?

...cb37dff0 Step 3 : RUN pip install -r requirements.txt ---> Running in 4b7a85a64c33 Downloading/unpacking pytest==2.3.4 (from -r requirements.txt (line 1)) Running setup.py (path:/tmp/pip_build_root/pytest/setup.py) egg_info for package pytest Downloading/unpacking ipython (from -r requirements...