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History of Idiom 20 > diff from v7 to v8

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Version 7

2015-08-19, 17:37:37

Version 8

2015-08-20, 10:48:55

Idiom #20 Return two values

Implement a function search which looks for item x in a 2D matrix m.
Return indices i, j of the matching cell.
Think of the most idiomatic way in the language to return the two values at the same time.

Idiom #20 Return two values

Implement a function search which looks for item x in a 2D matrix m.
Return indices i, j of the matching cell.
Think of the most idiomatic way in the language to return the two values at the same time.

Imports 
#include <string.h>
Code 
void search(void ***m,void *x,size_t memb_size,int len_x,int len_y,int *i,int *j)
{
	for(*i=0;*i<len_x;*i+=1)
	{
		for(*j=0;*j<len_y;*j+=1)
		{
			if(!memcmp(m[*i][*j],x,memb_size))
			{
				return;
			}
		}
	}
	*i=*j=-1;
}
Comments bubble
m is a matrix containing type (void *) pointing to the data (can be anyting)

x is the pointer to the data to look for

memb_size is the size of one element in bytes (to be able to compare anything)

len_x and len_y are the dimensions

i and j are passed by reference and contain the values, or -1 if x was not found, after the function returned.