C language, grouping elements in an array

Question

My code is far too long, complicated and tedious for me to post it here, but suppose you had something like this:

    #include <stdio.h>

char myArray[3000]={3,1,3,1,2,5,1,1,7,0,1,3,0,1,2,0,1,6,0,1,8,9,1,0,0,1,4,3,1,7};

Suppose I wanted to make a new array that takes the two consecutive digits from the above list of elements.

indexes 2-6 of myArray contain (3,1,2,5), how can I get my new array to group elements and store elements 2-6 as (31, 25).

I'm new to programming and I haven't found an efficient way of doing this.

Answer 1

Simplest way to think about it:

int newArray[2];
newArray[0] = myArray[2]*10 + myArray[3];
newArray[1] = myArray[4]*10 + myArray[5];

If you wanted something more generic...

#define NEW_ARRAY_SIZE 5
int newArray[NEW_ARRAY_SIZE];
int offset = 2;
int i = 0;
for ( i = 0; i < NEW_ARRAY_SIZE; ++i )
{
   newArray[i] = myArray[offset+2*i]*10 + myArray[offset+2*i+1];
}