Data commit

Task/Gray-code/C/gray-code-1.c

@@ -0,0 +1,9 @@
+int gray_encode(int n) {
+    return n ^ (n >> 1);
+}
+
+int gray_decode(int n) {
+    int p = n;
+    while (n >>= 1) p ^= n;
+    return p;
+}

Task/Gray-code/C/gray-code-2.c

@@ -0,0 +1,24 @@
+#include <stdio.h>
+
+/* Simple bool formatter, only good on range 0..31 */
+void fmtbool(int n, char *buf) {
+    char *b = buf + 5;
+    *b=0;
+    do {
+	*--b = '0' + (n & 1);
+	n >>= 1;
+    } while (b != buf);
+}
+
+int main(int argc, char **argv) {
+    int i,g,b;
+    char bi[6],bg[6],bb[6];
+
+    for (i=0 ; i<32 ; i++) {
+	g = gray_encode(i);
+	b = gray_decode(g);
+	fmtbool(i,bi); fmtbool(g,bg); fmtbool(b,bb);
+	printf("%2d : %5s => %5s => %5s : %2d\n", i, bi, bg, bb, b);
+    }
+    return 0;
+}