priority queue stl cmp function explain plz

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In the C++ Standard Template Library (STL), a priority queue is a container adapter that provides constant time lookup of the largest (or smallest) element in the collection, and logarithmic time insertion and extraction of elements from anywhere within the collection.

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When creating a priority queue, you can provide a custom comparison function object to determine the ordering of elements. This comparison function object must be a binary predicate that takes two arguments and returns a boolean value indicating whether the first argument should come before the second in the ordering.

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Here's an example of a custom comparison function object for a priority queue of integers that orders the elements in decreasing order:

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csharp

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struct CompareInt {

  bool operator()(const int& a, const int& b) const {

    return a > b;

  }

};

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In this example, the operator() function returns true if a should come before b in the ordering (i.e., if a is greater than b). This means that when elements are inserted into the priority queue, they will be sorted in decreasing order.

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You can then create a priority queue using this custom comparison function object as follows:

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c

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std::priority_queue<int, std::vector<int>, CompareInt> pq;

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In this example, the third argument to the std::priority_queue template specifies the custom comparison function object to use.

cmp file1.txt file2.txt # Indicates differences between 2 files

#Options

# -b -> displays differing bytes in output

# -i 10:12 -> indicating that both files are identical after 10 bytes

# skipped from first file and 12 bytes skipped from second file

# -l -> print byte position and byte value for all differing bytes.

# -s -> without displaying the differing byte and line

# -n 50 -> indicating files are identical for starting 50 bytes

# -v -> gives the output information and exits