The comparison function of sort in c++<algorithm>

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The comparison function of the sort in c++<algorithm>, the need for friends can refer to the next.

To define a sort function:

Method 1: Declare an external comparison function

BOOL Less (constconst student& s2) {    return// from small to large } Std::sort (Sutvector.begin (), Stuvector.end (), less);

Note: The comparison function must be written outside the class (global zone) or declared as a static function

When comp is a member function of a class, the default has a this pointer, which is different from the sort function type that the sort function needs to use.

Otherwise, an error will occur

Method 2: Overloading the class's comparison operators

BOOL operator< (constconst student& s2) {    return//  From small to large sort }std::sort (Sutvector.begin (), Stuvector.end ());

Method 3: Declare the comparison class

struct less{    booloperator() (constconst student& s2)    {         return// from small to large sort     }};std::sort (Sutvector.begin (), Stuvector.end (), Less ());

Comparison function notation for sort in c++<algorithm> (RPM)