C++ Tutorial/STL Algorithms Min Max/max element

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Find and print maximum elements in a vector

/* The following code example is taken from the book
 * "The C++ Standard Library - A Tutorial and Reference"
 * by Nicolai M. Josuttis, Addison-Wesley, 1999
 *
 * (C) Copyright Nicolai M. Josuttis 1999.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 */
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main()
{
    vector<int> coll;
    vector<int>::iterator pos;
    // insert elements from 1 to 6 in arbitrary order
    coll.push_back(2);
    coll.push_back(5);
    coll.push_back(4);
    coll.push_back(1);
    coll.push_back(6);
    coll.push_back(3);
    // find and print maximum elements
    pos = max_element (coll.begin(), coll.end());
    cout << "max: " << *pos << endl;
}
max: 6

Use max_element to get the maximum element in a container

/* The following code example is taken from the book
 * "The C++ Standard Library - A Tutorial and Reference"
 * by Nicolai M. Josuttis, Addison-Wesley, 1999
 *
 * (C) Copyright Nicolai M. Josuttis 1999.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 */
#include <cstdlib>
#include <iostream>
#include <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* PRINT_ELEMENTS()
 * - prints optional C-string optcstr followed by
 * - all elements of the collection coll
 * - separated by spaces
 */
template <class T>
inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="")
{
    typename T::const_iterator pos;
    std::cout << optcstr;
    for (pos=coll.begin(); pos!=coll.end(); ++pos) {
        std::cout << *pos << " ";
    }
    std::cout << std::endl;
}
/* INSERT_ELEMENTS (collection, first, last)
 * - fill values from first to last into the collection
 * - NOTE: NO half-open range
 */
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
    for (int i=first; i<=last; ++i) {
        coll.insert(coll.end(),i);
    }
}
using namespace std;
int main()
{
    deque<int> coll;
    INSERT_ELEMENTS(coll,2,8);
    INSERT_ELEMENTS(coll,-3,5);
    PRINT_ELEMENTS(coll);
    //maximum
    cout << "maximum: "
         << *max_element(coll.begin(),coll.end())
         << endl;
}
2 3 4 5 6 7 8 -3 -2 -1 0 1 2 3 4 5
maximum: 8

Use max_element to get the maximum value

#include <algorithm>
#include <functional>
#include <iomanip>
#include <iostream>
#include <vector>
using namespace std;
int main(){
   const float a[] = { 13.4, 27.6, 15.5, 44.3, 51.2, 30.2, 18.0 };
   vector<float> data( a,a + sizeof( a ) / sizeof( a[0] ) );
   float data_min = *min_element( data.begin(), data.end() );
   float data_max = *max_element( data.begin(), data.end() );
   cout << data_max;
}

Use max_element with criteria function

/* The following code example is taken from the book
 * "The C++ Standard Library - A Tutorial and Reference"
 * by Nicolai M. Josuttis, Addison-Wesley, 1999
 *
 * (C) Copyright Nicolai M. Josuttis 1999.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 */
#include <cstdlib>
#include <iostream>
#include <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* PRINT_ELEMENTS()
 * - prints optional C-string optcstr followed by
 * - all elements of the collection coll
 * - separated by spaces
 */
template <class T>
inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="")
{
    typename T::const_iterator pos;
    std::cout << optcstr;
    for (pos=coll.begin(); pos!=coll.end(); ++pos) {
        std::cout << *pos << " ";
    }
    std::cout << std::endl;
}
/* INSERT_ELEMENTS (collection, first, last)
 * - fill values from first to last into the collection
 * - NOTE: NO half-open range
 */
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
    for (int i=first; i<=last; ++i) {
        coll.insert(coll.end(),i);
    }
}
using namespace std;

bool absLess (int elem1, int elem2)
{
    return abs(elem1) < abs(elem2);
}

int main()
{
    deque<int> coll;
    INSERT_ELEMENTS(coll,2,8);
    INSERT_ELEMENTS(coll,-3,5);
    PRINT_ELEMENTS(coll);
    cout << "maximum of absolute values: "
         << *max_element(coll.begin(),coll.end(),
                         absLess)
         << endl;
}
2 3 4 5 6 7 8 -3 -2 -1 0 1 2 3 4 5
maximum of absolute values: 8