1 files changed, 2 insertions, 2 deletions
diff --git a/diff.awk b/diff.awk
index 1e6a882..64df9fb 100644
--- a/diff.awk
+++ b/diff.awk
@@ -21,11 +21,11 @@ NR == 1 {
     for (n=1; n<=NF; n++) {
         if ($n !~ number) {
             header[n] = $n
-            dheader[n] = "d" $n
+            dheader[n] = "d_" $n
         }
         else {
             header[n] = "col" n
-            dheader[n] = "dcol" n
+            dheader[n] = "d_col" n
         }
         printf(header[n])
         printf(OFS)