Search and Sort in an array

[Tchriss99]

I have an array which is as follows:

1 2 8
-1 -2 3
-1 1 4
-2 -1 2

I wan to do a search for the smallest value according to the last column. IOW I want to select 2 and return the values -2,-1.

Thanks for the help.

 

[aphrodita]

Convert this double array into single one, so you have it like this:

1 2 8 -1 -2 3 -1 1 4 -2 -1 2

then sort it the way one would sort one dimensional array, picking 2 last elements if its going to be descending. Best Regards,

aphrodita@mail.krovatka.ru {uiuc rules}

http://www.hellforge.org

 

[tootired]

No need to convert to a one-dimensional array, surely. Plus that might obscure the purpose of the array.

Here's a simple treatment.

int myarray[ NOROWS ][ NOCOLS ];

getvalues( int* p1, int* p2 )
{
int row, returnrow, minvalue;

row = 0;
*p1 = myarray[ row ][ 0 ];
*p2 = myarray[ row ][ 1 ];
minvalue = myarray[ row ][ 2 ];

for( row = 1; row < NOROWS; row++ )
{
if( minvalue > myarray[ row ][ 2 ] )
{
*p1 = myarray[ row ][ 0 ];
*p2 = myarray[ row ][ 1 ];
minvalue = myarray[ row ][ 2 ];
}
}
}

Best wishes,

tootired

 

[aphrodita]

The problem is sorting the 2-dim array, which your treatment does not show. Converting it to 1-dim, sorting, converting back is a solution that does not require much manipulation. Best Regards,

aphrodita@mail.krovatka.ru {uiuc rules}

http://www.hellforge.org

 

[tootired]

I think we're answering different questions! My reading of the original question is that we don't want to sort the whole array - we want to find the minimum value in the third column, and then return the corresponding values in the first two columns.

The example given is that the &quot;lookup&quot; value is 2, and the returned values are -1, -2. Your sorting approach leaves two -2 values.

So IMHO my answer is right, and your answer is right to the question &quot;I've got a two dimensional array and I want to know the lowest 2 values held in it&quot;.

Happy New Year!

tootired

 

[aphrodita]

You are right, thanks for explaining. Best Regards,

aphrodita@mail.krovatka.ru {uiuc rules}

http://www.hellforge.org