Source of generate_n1a.cpp

Structures and functions

  1: //generate_n1a.cpp

  3: #include <iostream>
  4: #include <vector>
  5: #include <algorithm>
  6: #include <cstdlib>
  7: using namespace std;

  9: int main()
 10: {
 11:     cout << "\nThis program illustrates the use of the STL generate_n() "
 12:         "algorithm to fill\na range of values starting at a given "
 13:         "location in a vector of integers with\na specified number of "
 14:         "values generated by the rand() function from <cstdlib>.";
 15:     cout << "\nPress Enter to continue ... ";  cin.ignore(80, '\n');

 17:     vector<int> v(10);

 19:     cout << "\nHere are the initial contents of v:\n";
 20:     for (vector<int>::size_type i=0; i<v.size(); i++)
 21:         cout << v.at(i) << " ";
 22:     cout << "\nPress Enter to continue ... ";  cin.ignore(80, '\n');

 24:     cout << "\nNow we generate 6 random integer values and place them "
 25:         "\ninto the vector, starting at location 3.";
 26:     generate_n(v.begin()+2, 6, rand);
 27:     cout << "\nHere are the revised contents of v:\n";
 28:     for (vector<int>::size_type i=0; i<v.size(); i++)
 29:         cout << v.at(i) << " ";
 30:     cout << "\nPress Enter to continue ... ";  cin.ignore(80, '\n');

 32:     cout << "\nFinally, we fill v with newly generated random "
 33:         "integer values.";
 34:     generate_n(v.begin(), (int)v.size(), rand);
 35:     cout << "\nHere are the revised contents of v:\n";
 36:     for (vector<int>::size_type i=0; i<v.size(); i++)
 37:         cout << v.at(i) << " ";
 38:     cout << "\nPress Enter to continue ... ";  cin.ignore(80, '\n');
 39: }