algo/search2.cpp

The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis


#include "algostuff.hpp"
using namespace std;

// checks whether an element is even or odd
bool checkEven (int elem, bool even)
{
    if (even) {
        return elem % 2 == 0;
    }
    else {
        return elem % 2 == 1;
    }
}

int main()
{
    vector<int> coll;

    INSERT_ELEMENTS(coll,1,9);
    PRINT_ELEMENTS(coll,"coll: ");

    // arguments for checkEven()
    // - check for: "even odd even"
    bool checkEvenArgs[3] = { true, false, true };

    // search first subrange in coll
    vector<int>::iterator pos;
    pos = search (coll.begin(), coll.end(),       // range
                  checkEvenArgs, checkEvenArgs+3, // subrange values
                  checkEven);                     // subrange criterion

    // loop while subrange found
    while (pos != coll.end()) {
        // print position of first element
        cout << "subrange found starting with element "
             << distance(coll.begin(),pos) + 1
             << endl;

        // search next subrange in coll
        pos = search (++pos, coll.end(),              // range
                      checkEvenArgs, checkEvenArgs+3, // subr. values
                      checkEven);                     // subr. criterion
    }
}