Data commit

Task/Letter-frequency/XPL0/letter-frequency.xpl0

@@ -0,0 +1,19 @@
+include c:\cxpl\codes;          \intrinsic 'code' declarations
+int A(256), C, I;
+[for C:= 0 to 256-1 do A(C):= 0;
+repeat  C:= ChIn(1);            \device 1 doesn't buffer nor echo chars
+        A(C):= A(C)+1;          \count character
+until   C=\EOF\$1A;
+C:= 0;
+for I:= 0 to 128-1 do           \only show 7-bit ASCII
+        [ChOut(0, \tab\9);
+        case C of
+          $0A: ChOut(6, $19);   \line feed = down arrow
+          $0D: ChOut(6, $1B)    \carriage return = left arrow
+        other  ChOut(6, C);     \all other characters display on device 6
+        ChOut(0, ^ );
+        IntOut(0, A(C));        \show count
+        C:= C+16;               \columnar order
+        if (I&7) = 7 then [CrLf(0);  C:= C-8*16+1];
+        ];
+]