diff --git a/challenges/triangle-type/README.md b/challenges/triangle-type/README.md
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+# triangle-type
+
+Created by [@Divlo](https://github.com/Divlo) on 30 June 2021.
+
+## Instructions
+
+Given the lengths of the 3 sides of a triangle, your function should return whether it is `equilateral`, `isosceles`, `scalene` or `impossible`.
+
+- A triangle is `equilateral` when its 3 sides are equal
+- A triangle is `isosceles` when 2 of its sides are equal
+- A triangle is `scalene` when none of its sides is equal to another side
+- A triangle is `impossible` when the sum of two of its sides is strictly less than the third side
+
+## Input
+
+- **Line 1 to 3:** The length of each side of the triangle
+
+## Examples
+
+See the `test` folder for examples of input/output.
diff --git a/challenges/triangle-type/solutions/.gitkeep b/challenges/triangle-type/solutions/.gitkeep
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index 0000000..e69de29
diff --git a/challenges/triangle-type/test/1/input.txt b/challenges/triangle-type/test/1/input.txt
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index 0000000..84e48a1
--- /dev/null
+++ b/challenges/triangle-type/test/1/input.txt
@@ -0,0 +1,3 @@
+2
+2
+2
\ No newline at end of file
diff --git a/challenges/triangle-type/test/1/output.txt b/challenges/triangle-type/test/1/output.txt
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index 0000000..5d69f76
--- /dev/null
+++ b/challenges/triangle-type/test/1/output.txt
@@ -0,0 +1 @@
+equilateral
\ No newline at end of file
diff --git a/challenges/triangle-type/test/10/input.txt b/challenges/triangle-type/test/10/input.txt
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index 0000000..bcff83a
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+++ b/challenges/triangle-type/test/10/input.txt
@@ -0,0 +1,3 @@
+7
+3
+2
\ No newline at end of file
diff --git a/challenges/triangle-type/test/10/output.txt b/challenges/triangle-type/test/10/output.txt
new file mode 100644
index 0000000..0a61a2f
--- /dev/null
+++ b/challenges/triangle-type/test/10/output.txt
@@ -0,0 +1 @@
+impossible
\ No newline at end of file
diff --git a/challenges/triangle-type/test/11/input.txt b/challenges/triangle-type/test/11/input.txt
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index 0000000..46898bc
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+++ b/challenges/triangle-type/test/11/input.txt
@@ -0,0 +1,3 @@
+10
+1
+3
\ No newline at end of file
diff --git a/challenges/triangle-type/test/11/output.txt b/challenges/triangle-type/test/11/output.txt
new file mode 100644
index 0000000..0a61a2f
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+++ b/challenges/triangle-type/test/11/output.txt
@@ -0,0 +1 @@
+impossible
\ No newline at end of file
diff --git a/challenges/triangle-type/test/12/input.txt b/challenges/triangle-type/test/12/input.txt
new file mode 100644
index 0000000..7218b68
--- /dev/null
+++ b/challenges/triangle-type/test/12/input.txt
@@ -0,0 +1,3 @@
+97
+97
+97
\ No newline at end of file
diff --git a/challenges/triangle-type/test/12/output.txt b/challenges/triangle-type/test/12/output.txt
new file mode 100644
index 0000000..5d69f76
--- /dev/null
+++ b/challenges/triangle-type/test/12/output.txt
@@ -0,0 +1 @@
+equilateral
\ No newline at end of file
diff --git a/challenges/triangle-type/test/2/input.txt b/challenges/triangle-type/test/2/input.txt
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index 0000000..ad94ab9
--- /dev/null
+++ b/challenges/triangle-type/test/2/input.txt
@@ -0,0 +1,3 @@
+10
+10
+10
\ No newline at end of file
diff --git a/challenges/triangle-type/test/2/output.txt b/challenges/triangle-type/test/2/output.txt
new file mode 100644
index 0000000..5d69f76
--- /dev/null
+++ b/challenges/triangle-type/test/2/output.txt
@@ -0,0 +1 @@
+equilateral
\ No newline at end of file
diff --git a/challenges/triangle-type/test/3/input.txt b/challenges/triangle-type/test/3/input.txt
new file mode 100644
index 0000000..16930b0
--- /dev/null
+++ b/challenges/triangle-type/test/3/input.txt
@@ -0,0 +1,3 @@
+3
+4
+4
\ No newline at end of file
diff --git a/challenges/triangle-type/test/3/output.txt b/challenges/triangle-type/test/3/output.txt
new file mode 100644
index 0000000..72d391a
--- /dev/null
+++ b/challenges/triangle-type/test/3/output.txt
@@ -0,0 +1 @@
+isosceles
\ No newline at end of file
diff --git a/challenges/triangle-type/test/4/input.txt b/challenges/triangle-type/test/4/input.txt
new file mode 100644
index 0000000..8ef0e0d
--- /dev/null
+++ b/challenges/triangle-type/test/4/input.txt
@@ -0,0 +1,3 @@
+4
+3
+4
\ No newline at end of file
diff --git a/challenges/triangle-type/test/4/output.txt b/challenges/triangle-type/test/4/output.txt
new file mode 100644
index 0000000..72d391a
--- /dev/null
+++ b/challenges/triangle-type/test/4/output.txt
@@ -0,0 +1 @@
+isosceles
\ No newline at end of file
diff --git a/challenges/triangle-type/test/5/input.txt b/challenges/triangle-type/test/5/input.txt
new file mode 100644
index 0000000..d9347bc
--- /dev/null
+++ b/challenges/triangle-type/test/5/input.txt
@@ -0,0 +1,3 @@
+10
+10
+2
\ No newline at end of file
diff --git a/challenges/triangle-type/test/5/output.txt b/challenges/triangle-type/test/5/output.txt
new file mode 100644
index 0000000..72d391a
--- /dev/null
+++ b/challenges/triangle-type/test/5/output.txt
@@ -0,0 +1 @@
+isosceles
\ No newline at end of file
diff --git a/challenges/triangle-type/test/6/input.txt b/challenges/triangle-type/test/6/input.txt
new file mode 100644
index 0000000..af64121
--- /dev/null
+++ b/challenges/triangle-type/test/6/input.txt
@@ -0,0 +1,3 @@
+3
+4
+5
\ No newline at end of file
diff --git a/challenges/triangle-type/test/6/output.txt b/challenges/triangle-type/test/6/output.txt
new file mode 100644
index 0000000..dcadc9b
--- /dev/null
+++ b/challenges/triangle-type/test/6/output.txt
@@ -0,0 +1 @@
+scalene
\ No newline at end of file
diff --git a/challenges/triangle-type/test/7/input.txt b/challenges/triangle-type/test/7/input.txt
new file mode 100644
index 0000000..98f3e0b
--- /dev/null
+++ b/challenges/triangle-type/test/7/input.txt
@@ -0,0 +1,3 @@
+10
+11
+12
\ No newline at end of file
diff --git a/challenges/triangle-type/test/7/output.txt b/challenges/triangle-type/test/7/output.txt
new file mode 100644
index 0000000..dcadc9b
--- /dev/null
+++ b/challenges/triangle-type/test/7/output.txt
@@ -0,0 +1 @@
+scalene
\ No newline at end of file
diff --git a/challenges/triangle-type/test/8/input.txt b/challenges/triangle-type/test/8/input.txt
new file mode 100644
index 0000000..0ad6615
--- /dev/null
+++ b/challenges/triangle-type/test/8/input.txt
@@ -0,0 +1,3 @@
+5
+4
+2
\ No newline at end of file
diff --git a/challenges/triangle-type/test/8/output.txt b/challenges/triangle-type/test/8/output.txt
new file mode 100644
index 0000000..dcadc9b
--- /dev/null
+++ b/challenges/triangle-type/test/8/output.txt
@@ -0,0 +1 @@
+scalene
\ No newline at end of file
diff --git a/challenges/triangle-type/test/9/input.txt b/challenges/triangle-type/test/9/input.txt
new file mode 100644
index 0000000..9c46309
--- /dev/null
+++ b/challenges/triangle-type/test/9/input.txt
@@ -0,0 +1,3 @@
+1
+1
+3
\ No newline at end of file
diff --git a/challenges/triangle-type/test/9/output.txt b/challenges/triangle-type/test/9/output.txt
new file mode 100644
index 0000000..0a61a2f
--- /dev/null
+++ b/challenges/triangle-type/test/9/output.txt
@@ -0,0 +1 @@
+impossible
\ No newline at end of file