max()

Library:  Algorithms

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Algorithm that returns the maximum of a pair of values

#include <algorithm>

namespace std {
  template <class T>
  const T& max(const T&, const T&);

  template <class T, class Compare>
  const T& max(const T&, const T&, Compare);
}

The max() algorithm determines and returns the maximum of a pair of values. In the first case, T must satisfy the requirements of LessThanComparable. In the second case, the optional argument Compare defines a binary function object that can be used in place of the default operator<().

max() returns the first argument when the arguments are equal.

//
//  max.cpp
//

#include <algorithm>    // for max, min
#include <functional>   // for greater
#include <iostream>     // for cout


int main ()
{
    double d1 = 10.0, d2 = 20.0;

    // Find minimum.
    double val1 = std::min (d1, d2);

    // The greater comparator returns the greater of 
    // the two values.
    double val2 = std::min (d1, d2, std::greater<double>());

    // Find minimum.
    double val3 = std::max (d1, d2);

    // The less comparator returns the smaller of 
    // the two values.

    // Note that, like every comparison in the library, max is
    // defined in terms of the < operator, so using less here
    // is the same as using the max algorithm with a default
    // comparator.
    double val4 = std::max(d1, d2, std::less<double>());

    std::cout << val1 << " " << val2 << " "
              << val3 << " " << val4 << std::endl;

    return 0;
}


Program Output:

10 20 20 20

max_element(), min(), min_element()

ISO/IEC 14882:1998 -- International Standard for Information Systems -- Programming Language C++, Sections 25.3.7 and 20.1.2