iota

Stores a starting value, beginning with the first element and filling with successive increments of that value (_Value++) in each of the elements in the interval [_First, _Last).

template<class ForwardIterator, class Type> 
   void iota( 
      ForwardIterator _First,  
      ForwardIterator _Last, 
      Type _Value  
   );

Parameters

• _First
  An input iterator that addresses the first element in the range to be filled.

• _Last
  An input iterator that addresses the last element in the range to be filled.

• _Value
  The starting value to store in the first element and to successively increment for subsequent elements.

Example

The following example demonstrates some uses for the iota function by filling a list of integers and then filling a vector with the list so that the random_shuffle function can be used.

// compile by using: cl /EHsc /nologo /W4 /MTd
#include <algorithm>
#include <numeric>
#include <list>
#include <vector>
#include <iostream>

using namespace std;

int main(void)
{
    list <int> intList(10);
    vector <list<int>::iterator> intVec(intList.size());

    // Fill the list
    iota(intList.begin(), intList.end(), 0);

    // Fill the vector with the list so we can shuffle it
    iota(intVec.begin(), intVec.end(), intList.begin());

    random_shuffle(intVec.begin(), intVec.end());

    // Output results
    cout << "Contents of the integer list: " << endl;
    for (auto i: intList) {
        cout << i << ' ';
    }
    cout << endl << endl;

    cout << "Contents of the integer list, shuffled by using a vector: " << endl;
    for (auto i: intVec) {
        cout << *i << ' ';
    }
    cout << endl;
}

Output

Contents of the integer list:

0 1 2 3 4 5 6 7 8 9

Contents of the integer list, shuffled by using a vector:

8 1 9 2 0 5 7 3 4 6

Requirements

Header: <numeric>

Namespace: std

See Also

Reference

Standard Template Library