std::max

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Defined in header <algorithm>

template< class T >
const T& max( const T& a, const T& b );
(1)
template< class T, class Compare >
const T& max( const T& a, const T& b, Compare comp );
(2)
template< class T >
T max( std::initializer_list ilist);
(3) (C++11 feature)
template< class T, class Compare >
T max( std::initializer_list ilist, Compare comp );
(4) (C++11 feature)

1-2) Returns the greater of the two values.

3-4) Returns the greatest of the values in initializer list ilist.

The (1,3) versions use operator< to compare the values, the (2,4) versions use the given comparison function comp.

Contents

[edit] Parameters

a, b - the values to compare
ilist - initializer list with the values to compare
cmp - comparison function which returns ​true if if a is less than b.

The signature of the comparison function should be equivalent to the following:

bool cmp(const Type1 &a, const Type2 &b);

The signature does not need to have const &, but the function must not modify the objects passed to it.
The types Type1 and Type2 must be such that an object of type T can be implicitly converted to both of them. ​

[edit] Return value

1-2) The greater of a and b. If they are equivalent, returns a.

3-4) The greatest value in ilist. If several values are equivalent to the greatest, returns the leftmost one.

[edit] Complexity

1-2) Constant

3-4) Linear in ilist.size()

[edit] Equivalent function

[edit] Example

#include <algorithm>
#include <iostream>
 
int main()
{
    std::cout << "larger of 1 and 9999: " << std::max(1, 9999) << '\n';
    std::cout << "larger of 'a' and 'b': " << std::max('a', 'b') << '\n';
    std::cout << "larger of 3.5 and 2.5: " << std::max(3.5, 2.5) << '\n';
}

Output:

larger of 1 and 9999: 9999
larger of 'a' and 'b': b
larger of 3.5 and 2.5: 3.5

[edit] See also

min
returns the smaller of two elements
(function template)
minmax (C++11)
returns the larger and the smaller of two elements
(function template)
max_element
returns the largest element in a range
(function template)