简单选择排序（C & Java 实现）

C语言版 

#include <stdio.h>

#define SWAP( a, i, j ) { t = a[i]; a[i] = a[j]; a[j] = t; }

void disp_array( int a[], int n )
{
    int i;
    for( i = 0; i < n; ++i )    
        printf( "%d ", a[i] );
    printf( "\n" );
}

int select_min( int a[], int n, int i )
{
    int min_v = a[i], j, id = i;
    for( j = i + 1; j < n; ++j )
    {
        if( a[j] < min_v )
        {
            min_v = a[j]; id = j;
        }
    }
    return id;
}

void select_sort( int a[], int n )
{
    int i, id, t;
    for( i = 0; i < n; ++i )
    {
        id = select_min( a, n, i );
        if( i != id )
            SWAP( a, id, i );
    }
}

int main()
{
    int n = 8;
    int a[] = { 49, 38, 65, 97, 76, 13, 27, 49 };
    
    printf( "Before sorting: " );
    disp_array( a, n );
    
    select_sort( a, n );

    printf( "After sorting: " );
    disp_array( a, n );

    return 0;
} 

Java语言版

public class TestSort {
	
	public static void dispArray( int a[] ) {
		for( int i = 0; i < a.length; ++i )
			System.out.print( a[i] + " " );
		System.out.println();
	}
	
	public static void swap( int a[], int i, int j ) {
		int t = a[i]; a[i] = a[j]; a[j] = t;
	}
	
	private static boolean less( int a[], int i, int j ) {
		return a[i] < a[j];
	}
	
	private static boolean less( int a, int b ) {
		return a < b;
	}
	
	private static int selectMin( int [] a, int i, int j ) {
		if( i > j ) return -1;
		int minVal = a[i], minId = i;
		for( int k = i + 1; k <= j; ++k ) {
			if( less( a[k], minVal ) ) {
				minVal = a[k]; minId = k;
			}
		}
		return minId;
	}
	
	/*
	 * selection sort
	 */
	public static void selectSort( int [] a ) {
		int minId;
		for( int i = 0; i < a.length; ++i ) {
			minId = selectMin( a, i, a.length - 1 );
			if( i != minId ) swap( a, i, minId );
		}
	}
	
	public static void main( String[] args ) {
		int a[] = { 100, 49, 38, 65, 97, 76, 13, 27, 49 };
		System.out.print( "Before sorting: " );
		dispArray( a );
		selectSort( a );
		System.out.print( "Simple Selection sorting: " );
		dispArray( a );
	}
}