Data commit

Task/Gray-code/AWK/gray-code.awk

@@ -0,0 +1,37 @@
+# Tested using GAWK
+
+function bits2str(bits,        data, mask)
+{
+    # Source: https://www.gnu.org/software/gawk/manual/html_node/Bitwise-Functions.html
+    if (bits == 0)
+        return "0"
+
+    mask = 1
+    for (; bits != 0; bits = rshift(bits, 1))
+        data = (and(bits, mask) ? "1" : "0") data
+
+    while ((length(data) % 8) != 0)
+        data = "0" data
+
+    return data
+}
+
+function gray_encode(n){
+    # Source: https://en.wikipedia.org/wiki/Gray_code#Converting_to_and_from_Gray_code
+    return xor(n,rshift(n,1))
+}
+
+function gray_decode(n){
+    # Source: https://en.wikipedia.org/wiki/Gray_code#Converting_to_and_from_Gray_code
+    mask = rshift(n,1)
+    while(mask != 0){
+        n = xor(n,mask)
+        mask = rshift(mask,1)
+    }
+    return n
+}
+
+BEGIN{
+    for (i=0; i < 32; i++)
+        printf "%-3s => %05d => %05d => %05d\n",i, bits2str(i),bits2str(gray_encode(i)), bits2str(gray_decode(gray_encode(i)))
+}