C++ Programming Code Examples
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Returns the positions of all values within a range
/* Returns the positions of all values within a range */
#include <iostream>
#include <vector>
using namespace std;
vector<int> find_all_between(vector<double> v, double low, double high)
{
vector<int> pos;
for (int i = 0; i < v.size(); i++)
{
if (low <= v[i] && v[i] <= high)
pos.push_back(i);
}
return pos;
}
int main()
{
vector<double> salaries(5);
salaries[0] = 3.0;
salaries[1] = 6.0;
salaries[2] = 4.0;
salaries[3] = 7.0;
salaries[4] = 5.0;
vector<int> matches = find_all_between(salaries, 4.0, 6.0);
for (int j = 0; j < matches.size(); j++)
cout << salaries[matches[j]] << "\n";
return 0;
}
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Access element. Returns a reference to the element at position n in the vector container. A similar member function, vector::at, has the same behavior as this operator function, except that vector::at is bound-checked and signals if the requested position is out of range by throwing an out_of_range exception. Portable programs should never call this function with an argument n that is out of range, since this causes undefined behavior. Function returns the element at the specified position in the vector.
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.
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Add element at the end. Adds a new element at the end of the vector, after its current last element. The content of val is copied (or moved) to the new element. This effectively increases the container size by one, which causes an automatic reallocation of the allocated storage space if -and only if- the new vector size surpasses the current vector capacity. push_back() function is used to push elements into a vector from the back. The new value is inserted into the vector at the end, after the current last element and the container size is increased by 1. This function does not return any value.
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A program shall contain a global function named main, which is the designated start of the program in hosted environment. main() function is the entry point of any C++ program. It is the point at which execution of program is started. When a C++ program is executed, the execution control goes directly to the main() function. Every C++ program have a main() function.
Return size. Returns the number of elements in the vector. This is the number of actual objects held in the vector, which is not necessarily equal to its storage capacity. vector::size() is a library function of "vector" header, it is used to get the size of a vector, it returns the total number of elements in the vector. The dynamic array can be created by using a vector in C++. One or more elements can be inserted into or removed from the vector at the run time that increases or decreases the size of the vector. The size or length of the vector can be counted using any loop or the built-in function named size(). This function does not accept any parameter.
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Using Fibonacci numbers we calculate mid of data array to search the data item. 'Calculate' the mid of the array. Divide the array into two subarray. 'Compare the item' by mid element
'Memory allocated' for node dynamically and inserts element at beginning. Inserts elemnet at last. Inserts element at position and delete node at particular position. Update value of a
