- added sort package and test case

R=r
OCL=14975
CL=14975

diff --git a/src/lib/make.bash b/src/lib/make.bash
index f0f545f251f9c9ce52d5cdb0f10ed07aeff3cc8c..a9be5938b8787b2c222855ddbbd5ee0838b3e392 100755 (executable)
--- a/src/lib/make.bash
+++ b/src/lib/make.bash
@@ -7,7 +7,7 @@
 echo; echo; echo %%%% making lib %%%%; echo
 
 rm -f *.6
-for i in fmt.go flag.go container/vector.go
+for i in fmt.go flag.go container/vector.go sort.go
 do
        base=$(basename $i .go)
        echo 6g -o $GOROOT/pkg/$base.6 $i

diff --git a/src/lib/sort.go b/src/lib/sort.go
new file mode 100644 (file)
index 0000000..72b0ddd
--- /dev/null
+++ b/src/lib/sort.go
@@ -0,0 +1,95 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package Sort
+
+export type SortInterface interface {
+       len() int;
+       less(i, j int) bool;
+       swap(i, j int);
+}
+
+
+func Pivot(data SortInterface, a, b int) int {
+       // if we have at least 10 elements, find a better median
+       // by selecting the median of 3 elements and putting it
+       // at position a
+       if b - a >= 10 {
+               m0 := (a + b) / 2;
+               m1 := a;
+               m2 := b - 1;
+               // bubble sort on 3 elements
+               if data.less(m1, m0) { data.swap(m1, m0); }
+               if data.less(m2, m1) { data.swap(m2, m1); }
+               if data.less(m1, m0) { data.swap(m1, m0); }
+               // "m0 <= m1 <= m2"
+       }
+       
+       m := a;
+       for i := a + 1; i < b; i++ {
+               if data.less(i, a) {
+                       m++;
+                       data.swap(i, m);
+               }
+       }
+       data.swap(a, m);
+       
+       return m;
+}
+
+
+func Quicksort(data SortInterface, a, b int) {
+       if a + 1 < b {
+               m := Pivot(data, a, b);
+               Quicksort(data, 0, m);
+               Quicksort(data, m + 1, b);
+       }
+}
+
+
+export func Sort(data SortInterface) {
+       Quicksort(data, 0, data.len());
+}
+
+
+export func IsSorted(data SortInterface) bool {
+       n := data.len();
+       for i := n - 1; i > 0; i-- {
+               if data.less(i, i - 1) {
+                       return false;
+               }
+       }
+       return true;
+}
+
+
+// Convenience types for common cases
+// TODO: Once we can associate methods with all types, this can be simplified
+//       since we cann associate the methods with the arrays directly.
+
+export type IntArray struct {
+       data *[]int;
+}
+
+func (p *IntArray) len() int            { return len(p.data); }
+func (p *IntArray) less(i, j int) bool  { return p.data[i] < p.data[j]; }
+func (p *IntArray) swap(i, j int)       { p.data[i], p.data[j] = p.data[j], p.data[i]; }
+
+
+export type FloatArray struct {
+       data *[]float;
+}
+
+func (p *FloatArray) len() int            { return len(p.data); }
+func (p *FloatArray) less(i, j int) bool  { return p.data[i] < p.data[j]; }
+func (p *FloatArray) swap(i, j int)       { p.data[i], p.data[j] = p.data[j], p.data[i]; }
+
+
+export type StringArray struct {
+       data *[]string;
+}
+
+func (p *StringArray) len() int            { return len(p.data); }
+func (p *StringArray) less(i, j int) bool  { return p.data[i] < p.data[j]; }
+func (p *StringArray) swap(i, j int)       { p.data[i], p.data[j] = p.data[j], p.data[i]; }

diff --git a/test/sorting.go b/test/sorting.go
new file mode 100644 (file)
index 0000000..1619d83
--- /dev/null
+++ b/test/sorting.go
@@ -0,0 +1,62 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// $G $F.go && $L $F.$A && ./$A.out
+
+package main
+
+import Sort "sort"
+
+func main() {
+       {       data := []int{74, 59, 238, -784, 9845, 959, 905, 0, 0, 42, 7586, -5467984, 7586};
+               a := Sort.IntArray(&data);
+               
+               Sort.Sort(&a);
+
+               /*
+               for i := 0; i < len(data); i++ {
+                       print(data[i], " ");
+               }
+               print("\n");
+               */
+               
+               if !Sort.IsSorted(&a) {
+                       panic();
+               }
+       }
+
+       {       data := []float{74.3, 59.0, 238.2, -784.0, 2.3, 9845.768, -959.7485, 905, 7.8, 7.8};
+               a := Sort.FloatArray(&data);
+               
+               Sort.Sort(&a);
+
+               /*
+               for i := 0; i < len(data); i++ {
+                       print(data[i], " ");
+               }
+               print("\n");
+               */
+               
+               if !Sort.IsSorted(&a) {
+                       panic();
+               }
+       }
+
+       {       data := []string{"", "Hello", "foo", "bar", "foo", "f00", "%*&^*&^&", "***"};
+               a := Sort.StringArray(&data);
+               
+               Sort.Sort(&a);
+
+               /*
+               for i := 0; i < len(data); i++ {
+                       print(data[i], " ");
+               }
+               print("\n");
+               */
+               
+               if !Sort.IsSorted(&a) {
+                       panic();
+               }
+       }
+}