

The selection sort is a combination of searching and sorting.
During each pass, the unsorted element
with the smallest (or largest) value is moved to its proper
position in the array.
The number of times the sort passes through the array is
one less than the number of items in the array. In the
selection sort, the inner loop finds the next smallest (or
largest) value and the outer loop places that value into its
proper location. 
Let's look at our same table of elements using
a selection sort for descending order. Remember, a "pass" is
defined as one full trip through the array comparing and if
necessary, swapping elements. 
Array at
beginning: 
84 
69 
76 
86 
94 
91 
After
Pass #1: 
84 
91 
76 
86 
94 
69 
After
Pass #2: 
84 
91 
94 
86 
76 
69 
After
Pass #3: 
86 
91 
94 
84 
76 
69 
After
Pass #4: 
94 
91 
86 
84 
76 
69 
After
Pass #5 (done): 
94 
91 
86 
84 
76 
69 
While being an easy sort to program, the selection sort is one of the
least efficient.
The algorithm offers no way to end the sort early,
even if it begins with an already sorted list.
// Selection Sort Method for
Descending Order
public static void SelectionSort ( int [ ]
num )
{
int i, j, first, temp;
for ( i = num.length  1; i > 0; i   )
{
first = 0; //initialize to
subscript of first element
for(j = 1; j <= i; j
++) //locate smallest
element between 1 and i.
{
if(
num[
j ] < num[ first ] )
first = j;
}
temp = num[ first ]; //swap
smallest found with element in position i.
num[ first ] = num[
i ];
num[ i ] = temp;
}
} 
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