RosettaCodeData/Task/Find-the-missing-permutation/Aime/find-the-missing-permutation.aime

void
paste(record r, index x, text p, integer a)
{
    p = insert(p, -1, a);
    x.delete(a);
    if (~x) {
        x.vcall(paste, -1, r, x, p);
    } else {
        r[p] = 0;
    }
    x[a] = 0;
}

integer
main(void)
{
    record r;
    list l;
    index x;

    l.bill(0, "ABCD", "CABD", "ACDB", "DACB", "BCDA", "ACBD", "ADCB",
           "CDAB", "DABC", "BCAD", "CADB", "CDBA", "CBAD", "ABDC", "ADBC",
           "BDCA", "DCBA", "BACD", "BADC", "BDAC", "CBDA", "DBCA", "DCAB");

    x['A'] = x['B'] = x['C'] = x['D'] = 0;

    x.vcall(paste, -1, r, x, "");

    l.ucall(r_delete, 1, r);

    o_(r.low, "\n");

    return 0;
}