#include <stdio.h>
 
void Sort( int* arr,int n,bool(*cmp)(int,int) )
{
    for( int i=0; i<n-1; i++ )
    {
        for( int j=i+1; j<n; j++ )
        {
            if( cmp(arr[i],arr[j]) )
                swap( arr[i],arr[j] );
        }
    }
}
 
int ascending( int a,int b ) { return a > b; }    // greater
int descending( int a,int b ) { return a < b; }   // less
 
void main()
{
    int arr[10] = { 1,3,5,7,9,2,4,6,8,10 };
 
    // ascending
    Sort( arr,10,ascending );
    for( int i=0; i<10; i++ )
        printf( "%d ",arr[i] );
 
    printf( "\n" );
 
 
    // descending
    Sort( arr,descending );
    for( int i=0; i<10; i++ )
        printf( "%d ",arr[i] );
 
    printf( "\n" );
}

所以我在下面的例子中编写了一些源代码,期望得到相同的结果：

#include <iostream>
#include <algorithm>    // for sort
#include <functional>   // for less & greater
using namespace std;
 
bool gt( int a,int b ) { return a > b; }   // greater
bool ls( int a,int b ) { return a < b; }   // less
 
void main()
{
    int x[10] = { 1,10 };
 
    // ascending but descending
    sort( x,x+10,gt );
    for( int i=0; i<10; i++ )
        cout << x[i] << " ";
 
    cout << endl;
 
    // descending but ascending
    sort( x,ls );
    for( int i=0; i<10; i++ )
        cout << x[i] << " ";
 
    cout << endl;
 
 
    greater<int> g; // a > b
    less<int> l;    // a < b
 
    // ascending but descending
    sort( x,g );
    for( int i=0; i<10; i++ )
        cout << x[i] << " ";
 
    cout << endl;
 
    // descending but ascending
    sort( x,l );
    for( int i=0; i<10; i++ )
        cout << x[i] << " ";
 
    cout << endl;
}

但我的期望并不正确.

为什么在STL中排序不像C中的排序？