C++ Programming Code Examples
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Extends a unary_function
/* Extends a unary_function */
#include <algorithm>
#include <functional>
#include <vector>
#include <iostream>
using namespace std;
class MinMax : public unary_function<int, void>{
public:
MinMax();
void operator()(int elem);
int min, max;
protected:
bool first;
};
MinMax::MinMax() : min(-1), max(-1), first(true){}
void MinMax::operator()(int elem){
if (first) {
min = max = elem;
} else if (elem < min) {
min = elem;
} else if (elem > max) {
max = elem;
}
first = false;
}
int main(int argc, char** argv){
vector<int> myVector;
myVector.push_back(1);
myVector.push_back(2);
myVector.push_back(3);
MinMax func;
func = for_each(myVector.begin(), myVector.end(), func);
cout << "The max is " << func.max << endl;
cout << "The min is " << func.min << endl;
return (0);
}
Return iterator to end. Returns an iterator referring to the past-the-end element in the vector container. The past-the-end element is the theoretical element that would follow the last element in the vector. It does not point to any element, and thus shall not be dereferenced. Because the ranges used by functions of the standard library do not include the element pointed by their closing iterator, this function is often used in combination with vector::begin to specify a range including all the elements in the container. If the container is empty, this function returns the same as vector::begin. This function does not accept any parameter.
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#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.
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Consider a situation, when we have two persons with the same name, jhon, in the same class. Whenever we need to differentiate them definitely we would have to use some additional information along with their name, like either the area, if they live in different area or their mother's or father's name, etc. Same situation can arise in your C++ applications. For example, you might be writing some code that has a function called xyz() and there is another library available which is also having same function xyz(). Now the compiler has no way of knowing which version of xyz() function you are referring to within your code.
Return iterator to beginning. Returns an iterator pointing to the first element in the vector. Notice that, unlike member vector::front, which returns a reference to the first element, this function returns a random access iterator pointing to it. If the container is empty, the returned iterator value shall not be dereferenced. The C++ function std::vector::begin() returns a random access iterator pointing to the first element of the vector. This function does not accept any parameter.
In C++, constructor is a special method which is invoked automatically at the time of object creation. It is used to initialize the data members of new object generally. The constructor in C++ has the same name as class or structure. Constructors are special class functions which performs initialization of every object. The Compiler calls the Constructor whenever an object is created. Constructors initialize values to object members after storage is allocated to the object. Whereas, Destructor on the other hand is used to destroy the class object. • Default Constructor: A constructor which has no argument is known as default constructor. It is invoked at the time of creating object.
Divide the range into equal parts and assign a 'bucket' to each part. Split the data and insert them into the Corresponding bucket by using insertion sort. 'Merge' all the buckets into one
To improve "readability of program" make a separate function and function should return the "resultant number". In main function user enters input number. Calls the function, pass
