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POFind all possible arrays of size n constructed with all possible combinations of elements from another array in all possible orders?
 

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  1. POFind all possible arrays of size n constructed with all possible combinations of elements from another array in all possible orders?
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    <p>For an array A of arbitrary length n, I'd like to fill in a n x m array B with all combination of elements from A that includes all possible orders of those elements. For example, if A = {1, 2, 3} and m = 2, I'd like to get B as:</p> <p>11</p> <p>12</p> <p>13</p> <p>21</p> <p>22</p> <p>23</p> <p>31</p> <p>32</p> <p>33</p> <p>What is an efficient way to do this in C/C++? Thanks!</p> <p>EDIT: Here is what I figured out to work (data is within the class combs which is basically a matrix class with some added tricks):</p> <pre><code>void combs::setCombs (int arr[], int n, int m) { int z, tmp, repeat; int max = (int (pow(double (n), double( m )))); for (int i = 0; i &lt; m; i++) { z = 0; repeat = int (pow( double (n), double (i))); for (int j = 0; j &lt; repeat; j++) { for (int k = 0; k &lt; n; k ++) { for (int p = 0; p &lt; max/(n*repeat); p ++) { cout &lt;&lt; arr[k] &lt;&lt; endl; data[z*ROWS + i] = arr[k]; z++; } } } } } </code></pre>
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    1. USMichael LeVine
    1. USMichael LeVine
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    1. COAnd what have you tried? What worked? What didn't work? What problems have you encountered? Have you read the [Stack Overflow question checklist](http://meta.stackexchange.com/questions/156810/stack-overflow-question-checklist)?
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      1. POFind all possible arrays of size n constructed with all possible combinations of elements from another array in all possible orders?
      1. USSome programmer dude
    2. CO@rightfold I compile with g++, so C++.
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      1. POFind all possible arrays of size n constructed with all possible combinations of elements from another array in all possible orders?
      1. USMichael LeVine
 

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