The C++ Standard Library consists of the header, <numeric> which defines a collection of functions to perform certain operations on sequences of numeric values. accumulate() is a method in the STL that returns the result of accumulating all the values in the range specified for a given container.
Syntax:
accumulate( iterator_begin, iterator_end, init) //uses operator '+' to sum up the elements accumulate( iterator_begin, iterator_end, init, binary_op) // uses the given binary function op to work with elements
Parameters: The accumulate() method accepts 4 parameters
- iterator_begin: Iterator to the initial position
- iterator_end: Iterator to the final position ( Note: the range is [iterator_begin,iterator_end) )
- init: Initial value for accumulator
- binary_op: Binary operation function object that will be applied.
Return value: The result of accumulating all elements in the range
Example of accumulate() method
#include <iostream>
#include <numeric>
#include <vector>
using namespace std;
int main()
{
vector<int> v;
v.push_back(1);
v.push_back(2);
v.push_back(3);
v.push_back(4);
cout<<"Sum of elements: "<< accumulate( v.begin(), v.end(), 0 ) << endl;
cout<<"Product of elements: "<< accumulate( v.begin(), v.end(), 1, multiplies<int>() ) << endl;
}
Output:
Sum of elements: 10 Product of elements: 24
