Data commit

Task/Knuth-shuffle/Tcl/knuth-shuffle-1.tcl

@@ -0,0 +1,17 @@
+proc knuth_shuffle lst {
+   set j [llength $lst]
+   for {set i 0} {$j > 1} {incr i;incr j -1} {
+       set r [expr {$i+int(rand()*$j)}]
+       set t [lindex $lst $i]
+       lset lst $i [lindex $lst $r]
+       lset lst $r $t
+   }
+   return $lst
+}
+
+% knuth_shuffle {1 2 3 4 5}
+2 1 3 5 4
+% knuth_shuffle {1 2 3 4 5}
+5 2 1 4 3
+% knuth_shuffle {tom dick harry peter paul mary}
+tom paul mary harry peter dick

Task/Knuth-shuffle/Tcl/knuth-shuffle-2.tcl

@@ -0,0 +1,11 @@
+% for {set i 0} {$i<100000} {incr i} {
+    foreach val [knuth_shuffle {1 2 3 4 5}] pos {pos0 pos1 pos2 pos3 pos4} {
+        incr tots($pos) $val
+    }
+}
+% parray tots
+tots(pos0) = 300006
+tots(pos1) = 300223
+tots(pos2) = 299701
+tots(pos3) = 299830
+tots(pos4) = 300240