sorting - select sort

Posted 2022-12-11 小马识图

#include "stdio.h"
#include "string.h"

#define MAX_LIST 50


typedef struct _SqList 
    int data[MAX_LIST];
    int length;
SqList;

void swap( SqList* L,  unsigned index1, unsigned index2 )

    if( index1 >= L->length || index2 >= L->length ) return;

    if( index1 == index2 ) return;

    L->data[index1] = L->data[index1] ^ L->data[index2];

    L->data[index2] = L->data[index1] ^ L->data[index2];

    L->data[index1] = L->data[index1] ^ L->data[index2];


//Select sort is similar to bubble sort, but only swaps when necessary
//it at most swap one time for each position
void SelectSort(SqList* L)
   
    int i, j, minpos;   
    for( i = 0;  i < L->length - 1; i++ )
    
        //minpos saves the index of minimal value, initialize to i
         minpos = i; 
        //every outer loop pick the smallest from the rear of the array
        for( j = i + 1; j < L->length; j++ )
          

            //compare element at j and local minimal at minpos
            if( L->data[j] < L->data[minpos] )
            
                //update index only, no swapping
                //select sort saves the temporary minimal index,
                //whilst bubble sort saves the value at location i
                minpos = j;
            
        
        if( minpos != i ) 
            swap(L, i, minpos );
    


int main()

    SqList d;
    int intarr[] = 1,10,23,48,65,31,-21,9,88,100;
    memcpy( d.data, intarr, sizeof(intarr));
    d.length = sizeof(intarr)/sizeof(int);  
    int index = 0;
    printf("Original array:\\n");
    for( ; index < d.length; index++ )
        printf(" %d", d.data[index] );
    printf("\\nSelect sort...\\n");
    SelectSort( &d );
    for( index = 0; index < d.length; index++ )
        printf(" %d", d.data[index] );
    printf("\\n");
    return 0;