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How to merge 2 List and removing duplicate values from it in C#

...excludes duplicates from the return set. This is different behavior to the Concat method, which returns all the elements in the input sequences including duplicates. List<int> list1 = new List<int> { 1, 12, 12, 5}; List<int> list2 = new List<int> { 12, 5, 7, 9, 1 }; List<...
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Count the number of occurrences of a character in a string in Javascript

I need to count the number of occurrences of a character in a string. 33 Answers 33 ...
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Calling Objective-C method from C++ member function?

...d ); int doSomethingWith( void * aParameter ); void logMyMessage( char * aCStr ); private: void * self; }; #endif Notice the wrapper methods no longer require the void pointer to an instance of MyClass; it is now a private member of MyClassImpl. The init method is used to instantia...
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Remove all special characters from a string [duplicate]

...t titles that could contain anything and have them stripped of all special characters so they only have letters and numbers and of course I would like to replace spaces with hyphens. ...
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How to sort a dataFrame in python pandas by two or more columns?

... pd.DataFrame(np.random.randint(1, 5, (10,2)), columns=['a','b']) df1 = pd.concat([df1]*100000) def pdsort(df1): return df1.sort_values(['a', 'b'], ascending=[True, False]) def lex(df1): arr = df1.values return pd.DataFrame(arr[np.lexsort((-arr[:, 1], arr[:, 0]))]) assert (pdsort(df1)...
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What's the point of malloc(0)?

...que pointer that can be passed to free"), but if you're treating this as a char*, that may give you an invalid, non-terminated char. It could be dangerous to rely on this in cross-platform situations. – Reed Copsey Jan 7 '10 at 17:51 ...
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Finding the max value of an attribute in an array of objects

...nput in a array): var maxA = a.reduce((a,b)=>a.y>b.y?a:b).y; // 30 chars time complexity: O(n) var maxB = a.sort((a,b)=>b.y-a.y)[0].y; // 27 chars time complexity: O(nlogn) var maxC = Math.max(...a.map(o=>o.y)); // 26 chars time complexity: >O(2n) editable example her...
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Server.UrlEncode vs. HttpUtility.UrlEncode

...ou still need to // escape special characters yourself But my personal favorite has got to be HttpUtility.UrlPathEncode - this thing is really incomprehensible. It encodes: " " ==> "%20" "100% true" ==> "100%%20true" (ok, your url is broken now) "te...
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How to access pandas groupby dataframe by key

...ionally - turn it all back into a single dataframe object sampled_df = pd.concat(df_list, axis=0, join='outer') share | improve this answer | follow | ...
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Java executors: how to be notified, without blocking, when a task completes?

... { sleep(7000, TimeUnit.MILLISECONDS); /* Pretend to be busy... */ char[] str = new char[5]; ThreadLocalRandom current = ThreadLocalRandom.current(); for (int idx = 0; idx < str.length; ++idx) str[idx] = (char) ('A' + current.nextInt(26)); String msg = new String(str); ...