From 13c66f43444f165999ed3c4e31c87140a874094b Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Sun, 24 Mar 2024 16:19:42 +0000
Subject: [PATCH 01/13] feat/ generate exercise

---
 19_pascal/README.md                        |  3 +++
 19_pascal/pascal.js                        |  6 ++++++
 19_pascal/pascal.spec.js                   | 15 +++++++++++++++
 19_pascal/solution/pascal-solution.js      |  6 ++++++
 19_pascal/solution/pascal-solution.spec.js | 15 +++++++++++++++
 5 files changed, 45 insertions(+)
 create mode 100644 19_pascal/README.md
 create mode 100644 19_pascal/pascal.js
 create mode 100644 19_pascal/pascal.spec.js
 create mode 100644 19_pascal/solution/pascal-solution.js
 create mode 100644 19_pascal/solution/pascal-solution.spec.js

diff --git a/19_pascal/README.md b/19_pascal/README.md
new file mode 100644
index 00000000000..3753384515e
--- /dev/null
+++ b/19_pascal/README.md
@@ -0,0 +1,3 @@
+# Exercise 17 - pascal
+
+Description of the exercise goes here.
diff --git a/19_pascal/pascal.js b/19_pascal/pascal.js
new file mode 100644
index 00000000000..74d6a382f7a
--- /dev/null
+++ b/19_pascal/pascal.js
@@ -0,0 +1,6 @@
+const pascal = function() {
+  
+};
+  
+// Do not edit below this line
+module.exports = pascal;
diff --git a/19_pascal/pascal.spec.js b/19_pascal/pascal.spec.js
new file mode 100644
index 00000000000..f6cdd4f1ef9
--- /dev/null
+++ b/19_pascal/pascal.spec.js
@@ -0,0 +1,15 @@
+const pascal = require('./pascal');
+
+describe('pascal', () => {
+  test('First test description', () => {
+    // Replace this comment with any other necessary code, and update the expect line as necessary
+
+    expect(pascal()).toBe('');
+  });
+  
+  test.skip('Second test description', () => {
+    // Replace this comment with any other necessary code, and update the expect line as necessary
+
+    expect(pascal()).toBe('');
+  });
+});
diff --git a/19_pascal/solution/pascal-solution.js b/19_pascal/solution/pascal-solution.js
new file mode 100644
index 00000000000..951989be64c
--- /dev/null
+++ b/19_pascal/solution/pascal-solution.js
@@ -0,0 +1,6 @@
+const pascal = function() {
+  // Replace this comment with the solution code
+};
+  
+// Do not edit below this line
+module.exports = pascal;
diff --git a/19_pascal/solution/pascal-solution.spec.js b/19_pascal/solution/pascal-solution.spec.js
new file mode 100644
index 00000000000..419031927ff
--- /dev/null
+++ b/19_pascal/solution/pascal-solution.spec.js
@@ -0,0 +1,15 @@
+const pascal = require('./pascal-solution');
+
+describe('pascal', () => {
+  test('First test description', () => {
+    // Replace this comment with any other necessary code, and update the expect line as necessary
+
+    expect(pascal()).toBe('');
+  });
+  
+  test('Second test description', () => {
+    // Replace this comment with any other necessary code, and update the expect line as necessary
+
+    expect(pascal()).toBe('');
+  });
+});

From fbc74a68c57f297167f2d69fee664c5dabde6b3b Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Thu, 25 Apr 2024 20:22:54 +0100
Subject: [PATCH 02/13] feat(pascal): create solution

---
 19_pascal/solution/pascal-solution.js | 33 ++++++++++++++++++++++++---
 1 file changed, 30 insertions(+), 3 deletions(-)

diff --git a/19_pascal/solution/pascal-solution.js b/19_pascal/solution/pascal-solution.js
index 951989be64c..4bb70bd5435 100644
--- a/19_pascal/solution/pascal-solution.js
+++ b/19_pascal/solution/pascal-solution.js
@@ -1,6 +1,33 @@
-const pascal = function() {
-  // Replace this comment with the solution code
+const pascal = function (counter, currentLine = [1]) {
+  if (counter === 1) return currentLine;
+
+  const halfOfNextLine = currentLine.reduce(
+    (accumulator, currentElement, index, originalArray) => {
+      const nextElement = originalArray[index + 1]
+      if (currentElement <= nextElement) {
+        return [...accumulator, currentElement + nextElement];
+      }
+      return accumulator;
+    },
+    [1],
+  );
+
+  // Notice that pascal triangle's lines are always palindromic in nature. 
+  // We only need the first half to obtain the information to 
+  // Construct the second half
+  const joined = [...halfOfNextLine, ...halfOfNextLine.reverse()];
+
+  // If a given line of the pascal's triangle has an even amount of elements, two things are true:
+  // - the next line will have an odd amount of elements
+  // - the two elements in the middle will always be the same. So we are save to remove one
+  if (currentLine.length % 2 === 0) {
+    joined.splice(joined.length / 2, 1);
+  }
+
+  return pascal(counter - 1, joined);
 };
-  
+
+pascal(5)
+
 // Do not edit below this line
 module.exports = pascal;

From 0e00b590ba500220bed25f4b094a9040d9470e4b Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Thu, 25 Apr 2024 20:23:09 +0100
Subject: [PATCH 03/13] feat(pascal): create README.md

---
 19_pascal/README.md | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/19_pascal/README.md b/19_pascal/README.md
index 3753384515e..935a2445fff 100644
--- a/19_pascal/README.md
+++ b/19_pascal/README.md
@@ -1,3 +1,18 @@
-# Exercise 17 - pascal
+# Exercise 19 - pascal
 
-Description of the exercise goes here.
+The pascal's triangle is modelled as follows:
+- The first row is `1`.
+- Each row can be considered to have a hidden `0` to either sides of it. So the first row could
+also be said to be `0, 1, 0`
+- To obtain the next row, we take each number and add it with its rightmost neighbor.
+
+First row: `[1]`
+Second row: `[0+1, 1+0]` or simply `[1, 1]`
+Third row: `[0+1, 1+1, 1+0]` or simply `[1, 2, 1]`
+Fourth row: `[0+1, 1+2, 2+1, 1+0]` or simply `[1, 2, 2, 1]`
+... 
+
+The pattern continues forever.
+
+Your task is to create a *recursive* function, `pascal` - that will take an input `n` and output the 
+`n`th pascal's row.

From 8fe75f2c6e024f24620f14d874bc3dfec2d4a9f1 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Thu, 25 Apr 2024 20:23:26 +0100
Subject: [PATCH 04/13] feat(pascal): create tests for exercise

---
 19_pascal/solution/pascal-solution.spec.js | 32 ++++++++++++++++------
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/19_pascal/solution/pascal-solution.spec.js b/19_pascal/solution/pascal-solution.spec.js
index 419031927ff..41e072ddde1 100644
--- a/19_pascal/solution/pascal-solution.spec.js
+++ b/19_pascal/solution/pascal-solution.spec.js
@@ -1,15 +1,31 @@
 const pascal = require('./pascal-solution');
 
 describe('pascal', () => {
-  test('First test description', () => {
-    // Replace this comment with any other necessary code, and update the expect line as necessary
-
-    expect(pascal()).toBe('');
+  test('Gets the first row of pascal', () => {
+    expect(pascal(1)).toEqual([1]);
   });
   
-  test('Second test description', () => {
-    // Replace this comment with any other necessary code, and update the expect line as necessary
-
-    expect(pascal()).toBe('');
+  test('Gets the second row of pascal', () => {
+    expect(pascal(2)).toEqual([1, 1]);
+  });
+  
+  test('Gets the third row of pascal', () => {
+    expect(pascal(3)).toEqual([1, 2, 1]);
+  });
+  
+  test('Gets the fourth row of pascal', () => {
+    expect(pascal(4)).toEqual([1, 3, 3, 1]);
+  });
+  
+  test('Gets the fifth row of pascal', () => {
+    expect(pascal(5)).toEqual([1, 4, 6, 4, 1]);
+  });
+  
+  test('Gets the sixth row of pascal', () => {
+    expect(pascal(6)).toEqual([1, 5, 10, 10, 5, 1]);
+  });
+  
+  test('Gets the seventh row of pascal', () => {
+    expect(pascal(7)).toEqual([1, 6, 15, 20, 15, 6, 1]);
   });
 });

From 8608b4035e0bb301378c69419a1ccac11968a81f Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Fri, 3 May 2024 04:50:19 +0100
Subject: [PATCH 05/13] feat(pascal): remove unnecessary call to function

---
 19_pascal/solution/pascal-solution.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/19_pascal/solution/pascal-solution.js b/19_pascal/solution/pascal-solution.js
index 4bb70bd5435..cbea5e35ecb 100644
--- a/19_pascal/solution/pascal-solution.js
+++ b/19_pascal/solution/pascal-solution.js
@@ -27,7 +27,5 @@ const pascal = function (counter, currentLine = [1]) {
   return pascal(counter - 1, joined);
 };
 
-pascal(5)
-
 // Do not edit below this line
 module.exports = pascal;

From 26f5679b38bc06d59cb394a47fb2679683033bbe Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Sat, 29 Jun 2024 18:06:35 +0100
Subject: [PATCH 06/13] refactor: make code more readable

Co-authored-by: MaoShizhong <122839503+MaoShizhong@users.noreply.github.com>
---
 19_pascal/solution/pascal-solution.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/19_pascal/solution/pascal-solution.js b/19_pascal/solution/pascal-solution.js
index cbea5e35ecb..adbf0aaba57 100644
--- a/19_pascal/solution/pascal-solution.js
+++ b/19_pascal/solution/pascal-solution.js
@@ -1,5 +1,7 @@
 const pascal = function (counter, currentLine = [1]) {
-  if (counter === 1) return currentLine;
+  if (counter === 1) {
+    return currentLine;
+  }
 
   const halfOfNextLine = currentLine.reduce(
     (accumulator, currentElement, index, originalArray) => {

From c6291984208e831838e0ca8c5efa03bdb6c861c2 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Sat, 29 Jun 2024 18:08:52 +0100
Subject: [PATCH 07/13] refactor: remove unnecessary line break

Co-authored-by: MaoShizhong <122839503+MaoShizhong@users.noreply.github.com>
---
 19_pascal/solution/pascal-solution.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/19_pascal/solution/pascal-solution.js b/19_pascal/solution/pascal-solution.js
index adbf0aaba57..7bd43e8100a 100644
--- a/19_pascal/solution/pascal-solution.js
+++ b/19_pascal/solution/pascal-solution.js
@@ -15,8 +15,7 @@ const pascal = function (counter, currentLine = [1]) {
   );
 
   // Notice that pascal triangle's lines are always palindromic in nature. 
-  // We only need the first half to obtain the information to 
-  // Construct the second half
+  // We only need the first half to obtain the information to construct the second half
   const joined = [...halfOfNextLine, ...halfOfNextLine.reverse()];
 
   // If a given line of the pascal's triangle has an even amount of elements, two things are true:

From b5adfce302f2d9bfc717e3e8887797f93d7d3553 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Sun, 18 Aug 2024 16:27:52 +0100
Subject: [PATCH 08/13] feat(pascal): better names for variables

---
 19_pascal/solution/pascal-solution.js | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/19_pascal/solution/pascal-solution.js b/19_pascal/solution/pascal-solution.js
index 7bd43e8100a..d461f289084 100644
--- a/19_pascal/solution/pascal-solution.js
+++ b/19_pascal/solution/pascal-solution.js
@@ -4,17 +4,17 @@ const pascal = function (counter, currentLine = [1]) {
   }
 
   const halfOfNextLine = currentLine.reduce(
-    (accumulator, currentElement, index, originalArray) => {
-      const nextElement = originalArray[index + 1]
-      if (currentElement <= nextElement) {
-        return [...accumulator, currentElement + nextElement];
+    (numbers, currentNumber, index) => {
+      const nextNumber = currentLine[index + 1];
+      if (currentNumber <= nextNumber) {
+        return [...numbers, currentNumber + nextNumber];
       }
-      return accumulator;
+      return numbers;
     },
     [1],
   );
 
-  // Notice that pascal triangle's lines are always palindromic in nature. 
+  // Notice that pascal triangle's lines are always palindromic in nature.
   // We only need the first half to obtain the information to construct the second half
   const joined = [...halfOfNextLine, ...halfOfNextLine.reverse()];
 

From ca43c0029d2c7a09ae0db0c41a62b53325b9d2e4 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Sun, 18 Aug 2024 16:29:00 +0100
Subject: [PATCH 09/13] feat(pascal): math mistake

Co-authored-by: MaoShizhong <122839503+MaoShizhong@users.noreply.github.com>
---
 19_pascal/README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/19_pascal/README.md b/19_pascal/README.md
index 935a2445fff..c22aef7c2f3 100644
--- a/19_pascal/README.md
+++ b/19_pascal/README.md
@@ -9,7 +9,7 @@ also be said to be `0, 1, 0`
 First row: `[1]`
 Second row: `[0+1, 1+0]` or simply `[1, 1]`
 Third row: `[0+1, 1+1, 1+0]` or simply `[1, 2, 1]`
-Fourth row: `[0+1, 1+2, 2+1, 1+0]` or simply `[1, 2, 2, 1]`
+Fourth row: `[0+1, 1+2, 2+1, 1+0]` or simply `[1, 3, 3, 1]`
 ... 
 
 The pattern continues forever.

From d64601a8cfbfeecc855c7a7185f44363e279b0e9 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Tue, 20 Aug 2024 23:38:36 +0100
Subject: [PATCH 10/13] fix(pascal): typo

Co-authored-by: MaoShizhong <122839503+MaoShizhong@users.noreply.github.com>
---
 19_pascal/solution/pascal-solution.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/19_pascal/solution/pascal-solution.js b/19_pascal/solution/pascal-solution.js
index d461f289084..5e43d4391ef 100644
--- a/19_pascal/solution/pascal-solution.js
+++ b/19_pascal/solution/pascal-solution.js
@@ -20,7 +20,7 @@ const pascal = function (counter, currentLine = [1]) {
 
   // If a given line of the pascal's triangle has an even amount of elements, two things are true:
   // - the next line will have an odd amount of elements
-  // - the two elements in the middle will always be the same. So we are save to remove one
+  // - the two elements in the middle will always be the same. So it's safe to remove one
   if (currentLine.length % 2 === 0) {
     joined.splice(joined.length / 2, 1);
   }

From ad37314636638a3ce5414a849c763163493091f0 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Tue, 20 Aug 2024 23:39:40 +0100
Subject: [PATCH 11/13] feat(pascal): copy over tests from solution

---
 19_pascal/pascal.spec.js | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/19_pascal/pascal.spec.js b/19_pascal/pascal.spec.js
index f6cdd4f1ef9..d376f56bdee 100644
--- a/19_pascal/pascal.spec.js
+++ b/19_pascal/pascal.spec.js
@@ -1,15 +1,31 @@
 const pascal = require('./pascal');
 
 describe('pascal', () => {
-  test('First test description', () => {
-    // Replace this comment with any other necessary code, and update the expect line as necessary
+  test('Gets the first row of pascal', () => {
+    expect(pascal(1)).toEqual([1]);
+  });
+
+  test.skip('Gets the second row of pascal', () => {
+    expect(pascal(2)).toEqual([1, 1]);
+  });
+
+  test.skip('Gets the third row of pascal', () => {
+    expect(pascal(3)).toEqual([1, 2, 1]);
+  });
+
+  test.skip('Gets the fourth row of pascal', () => {
+    expect(pascal(4)).toEqual([1, 3, 3, 1]);
+  });
+
+  test.skip('Gets the fifth row of pascal', () => {
+    expect(pascal(5)).toEqual([1, 4, 6, 4, 1]);
+  });
 
-    expect(pascal()).toBe('');
+  test.skip('Gets the sixth row of pascal', () => {
+    expect(pascal(6)).toEqual([1, 5, 10, 10, 5, 1]);
   });
-  
-  test.skip('Second test description', () => {
-    // Replace this comment with any other necessary code, and update the expect line as necessary
 
-    expect(pascal()).toBe('');
+  test.skip('Gets the seventh row of pascal', () => {
+    expect(pascal(7)).toEqual([1, 6, 15, 20, 15, 6, 1]);
   });
 });

From f9bbd25c4638a5bfb22c6215caa1cd2f48433217 Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Sun, 25 Aug 2024 16:59:03 +0100
Subject: [PATCH 12/13] feat: remove line break

Co-authored-by: MaoShizhong <122839503+MaoShizhong@users.noreply.github.com>
---
 19_pascal/README.md | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/19_pascal/README.md b/19_pascal/README.md
index c22aef7c2f3..8d161fcfd13 100644
--- a/19_pascal/README.md
+++ b/19_pascal/README.md
@@ -2,8 +2,7 @@
 
 The pascal's triangle is modelled as follows:
 - The first row is `1`.
-- Each row can be considered to have a hidden `0` to either sides of it. So the first row could
-also be said to be `0, 1, 0`
+- Each row can be considered to have a hidden `0` to either sides of it. So the first row could also be said to be `0, 1, 0`
 - To obtain the next row, we take each number and add it with its rightmost neighbor.
 
 First row: `[1]`

From fc4bd94b47bf5daff94256a19ff855601cd5a26e Mon Sep 17 00:00:00 2001
From: Nikita Revenco <154856872+nikitarevenco@users.noreply.github.com>
Date: Sun, 25 Aug 2024 16:59:18 +0100
Subject: [PATCH 13/13] feat: remove line break

Co-authored-by: MaoShizhong <122839503+MaoShizhong@users.noreply.github.com>
---
 19_pascal/README.md | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/19_pascal/README.md b/19_pascal/README.md
index 8d161fcfd13..fa607c942ad 100644
--- a/19_pascal/README.md
+++ b/19_pascal/README.md
@@ -13,5 +13,6 @@ Fourth row: `[0+1, 1+2, 2+1, 1+0]` or simply `[1, 3, 3, 1]`
 
 The pattern continues forever.
 
-Your task is to create a *recursive* function, `pascal` - that will take an input `n` and output the 
-`n`th pascal's row.
+Your task is to create a *recursive* function, `pascal` - that will take an input `n` and output the `n`th pascal's row as an array of numbers.
+
+For example, `pascal(3)` should return `[1, 2, 1]`.