Data commit

Task/Superpermutation-minimisation/AWK/superpermutation-minimisation.awk

@@ -0,0 +1,48 @@
+# syntax: GAWK -f SUPERPERMUTATION_MINIMISATION.AWK
+# converted from C
+BEGIN {
+    arr[0] # prevents fatal: attempt to use scalar 'arr' as an array
+    limit = 11
+    for (n=0; n<=limit; n++) {
+      leng = super_perm(n)
+      printf("%2d %d ",n,leng)
+#     for (i=0; i<length(arr); i++) { printf(arr[i]) } # un-comment to see the string
+      printf("\n")
+    }
+    exit(0)
+}
+function fact_sum(n,  f,s,x) {
+    f = 1
+    s = x = 0
+    for (;x<n;) {
+      f *= ++x
+      s += f
+    }
+    return(s)
+}
+function super_perm(n,  i,leng) {
+    delete arr
+    pos = n
+    leng = fact_sum(n)
+    for (i=0; i<leng; i++) {
+      arr[i] = ""
+    }
+    for (i=0; i<=n; i++) {
+      cnt[i] = i
+    }
+    for (i=1; i<=n; i++) {
+      arr[i-1] = i + "0"
+    }
+    while (r(n)) { }
+    return(leng)
+}
+function r(n,  c) {
+    if (!n) { return(0) }
+    c = arr[pos-n]
+    if (!--cnt[n]) {
+      cnt[n] = n
+      if (!r(n-1)) { return(0) }
+    }
+    arr[pos++] = c
+    return(1)
+}