How can I use stable_sort function with structure?

[Master]

I cannot able to use the STL function stable_sort for sorting an array of structure. Could any one pls tell me how can I use it?

Thanks in advance
M H Rasel
CUET Old Sailor.

[Dominik Michniewski]

if I remember using sort functions with STL is involwed with writting class with special compare function ... look at i.e. MSDN library to check it ... but I don't know how it's in ANSI ....

Best regards
DM

[shamim]

Here is an example:

[cpp]


struct type
{
int age,gpa;

};
// defining comp
bool comp( const type &a, const type &b)
{
if ( a.age < b.age)
return true;
if ( a.age > b.age )
return false;
if ( a.gpa<b.gpa)
return true;

return false;
}

int main()
{
type a[20];
// take input
sort( a, a+10, comp) ;

}

[/cpp]

The above will sort the first ten elements first by checking age and if that is equal then by gpa.

[Krzysztof Duleba]

I think that the following solution is better:
[cpp]struct type{
int age,gpa;
bool operator<(const type& t){
return (age == t.age) ? (gpa < t.gpa) : (age < t.age);
}
};[/cpp]
and then:
[cpp]sort(a,a+10);[/cpp]
and when you want to do it in reverse order:
[cpp]sort(a,a+10,greater<type>());[/cpp]
(in that case, don't forget to include <functional>).

[Master]

Thanks a lot

M H Rasel
CUET Old Sailor