From 15c7a2787cf2fa94c14f3ad1e4ae37a83b3a44ed Mon Sep 17 00:00:00 2001
From: derek mcquay <derekmcquay@gmail.com>
Date: Fri, 12 Feb 2016 10:53:42 -0800
Subject: [PATCH] added detransposeSplit and tests

---
 psyfer/transposition.go      | 33 +++++++++++++++++++
 psyfer/transposition_test.go | 63 ++++++++++++++++++++++++++++++------
 2 files changed, 86 insertions(+), 10 deletions(-)

diff --git a/psyfer/transposition.go b/psyfer/transposition.go
index 4b097dd..570020e 100644
--- a/psyfer/transposition.go
+++ b/psyfer/transposition.go
@@ -43,3 +43,36 @@ func TransposeSplit(input string) string {
 	}
 	return split
 }
+
+func DeTransposeRailFence(input string) string {
+	rf := ""
+	for i := 0; i < len(input); i += 2 {
+		rf += string(input[i])
+	}
+	for i := 1; i < len(input); i += 2 {
+		rf += string(input[i])
+	}
+	return rf
+}
+
+func DeTransposeSplit(input string) string {
+	desplit := ""
+	if len(input)%2 == 0 {
+		for i := 0; i < len(input); i += 2 {
+			desplit += string(input[i])
+		}
+		for i := 1; i < len(input); i += 2 {
+			desplit += string(input[i])
+		}
+	} else {
+		for i := 0; i < len(input)-2; i += 2 {
+			desplit += string(input[i])
+		}
+		for i := 1; i < len(input)-2; i += 2 {
+			desplit += string(input[i])
+		}
+		//		fmt.Println(desplit)
+		desplit += string(input[len(input)-2]) + string(input[len(input)-1])
+	}
+	return desplit
+}
diff --git a/psyfer/transposition_test.go b/psyfer/transposition_test.go
index 3127ec9..dbd4574 100644
--- a/psyfer/transposition_test.go
+++ b/psyfer/transposition_test.go
@@ -8,7 +8,7 @@ func TestTransposeRailFence(t *testing.T) {
 	actual := TransposeRailFence(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeRailFence:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeRailFence:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -18,7 +18,7 @@ func TestTransposeRailFence(t *testing.T) {
 	actual = TransposeRailFence(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeRailFence:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeRailFence:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -28,7 +28,7 @@ func TestTransposeRailFence(t *testing.T) {
 	actual = TransposeRailFence(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeRailFence:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeRailFence:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -38,7 +38,7 @@ func TestTransposeRailFence(t *testing.T) {
 	actual = TransposeRailFence(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeRailFence:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeRailFence:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -51,7 +51,7 @@ func TestTransposeSplit(t *testing.T) {
 	actual := TransposeSplit(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeSplit:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeSplit:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -61,7 +61,7 @@ func TestTransposeSplit(t *testing.T) {
 	actual = TransposeSplit(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeSplit:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeSplit:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -71,7 +71,7 @@ func TestTransposeSplit(t *testing.T) {
 	actual = TransposeSplit(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeSplit:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeSplit:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -81,7 +81,7 @@ func TestTransposeSplit(t *testing.T) {
 	actual = TransposeSplit(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeSplit:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeSplit:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -91,7 +91,7 @@ func TestTransposeSplit(t *testing.T) {
 	actual = TransposeSplit(input)
 	if expected != actual {
 		t.Errorf(
-			"failed TransposeSplit:\n\texpected: % x\n\t  actual: % x",
+			"failed TransposeSplit:\n\texpected: % q\n\t  actual: % q",
 			expected,
 			actual,
 		)
@@ -103,9 +103,52 @@ func TestTransposeRandom(t *testing.T) {
 	actual := TransposeSplit(input)
 	if input == actual {
 		t.Errorf(
-			"failed TransposeRandom:\n\texpected: something random\n\t  actual: % x",
+			"failed TransposeRandom:\n\texpected: something random\n\t  actual: % q",
 			input,
 			actual,
 		)
 	}
 }
+
+func TestDeTransposeSplit(t *testing.T) {
+	expected := "helloworld"
+	input := "hweolrllod"
+	actual := DeTransposeSplit(input)
+	if expected != actual {
+		t.Errorf(
+			"failed DeTransposeSplit:\n\texpected: % q\n\t  actual: % q",
+			expected,
+			actual,
+		)
+	}
+	expected = "12"
+	input = "12"
+	actual = DeTransposeSplit(input)
+	if expected != actual {
+		t.Errorf(
+			"failed DeTransposeSplit:\n\texpected: % q\n\t  actual: % q",
+			expected,
+			actual,
+		)
+	}
+	expected = "12345"
+	input = "13245"
+	actual = DeTransposeSplit(input)
+	if expected != actual {
+		t.Errorf(
+			"failed DeTransposeSplit:\n\texpected: % q\n\t  actual: % q",
+			expected,
+			actual,
+		)
+	}
+	expected = "123"
+	input = "123"
+	actual = DeTransposeSplit(input)
+	if expected != actual {
+		t.Errorf(
+			"failed DeTransposeSplit:\n\texpected: % q\n\t  actual: % q",
+			expected,
+			actual,
+		)
+	}
+}