From 829e1bcffbd2041f126dd2fa0eda673afe68fb87 Mon Sep 17 00:00:00 2001
From: Rohit Dandnayak <rohit.dandnayak@ril.com>
Date: Thu, 4 Apr 2019 16:11:52 +0530
Subject: [PATCH 1/3] array data structure added

---
 src/data-structures/array/array-rotation.js | 18 ++++++++++++++++++
 src/data-structures/array/gcd-eucladian.js  |  7 +++++++
 2 files changed, 25 insertions(+)
 create mode 100644 src/data-structures/array/array-rotation.js
 create mode 100644 src/data-structures/array/gcd-eucladian.js

diff --git a/src/data-structures/array/array-rotation.js b/src/data-structures/array/array-rotation.js
new file mode 100644
index 000000000..e42533e3a
--- /dev/null
+++ b/src/data-structures/array/array-rotation.js
@@ -0,0 +1,18 @@
+function rotateArray(arr) {
+  let temp = arr[0];
+  let len = arr.length;
+  for (var i = 0; i < len - 1; i++) {
+    arr[i] = arr[i + 1];
+  }
+  arr[i] = temp;
+  return arr;
+}
+
+function rotateArrayBy(arr, d) {
+  for (let i = 0; i < d; i++) {
+    rotateArray(arr);
+  }
+  return arr;
+}
+
+console.log(rotateArrayBy([1, 2, 3, 4, 5], 2));
diff --git a/src/data-structures/array/gcd-eucladian.js b/src/data-structures/array/gcd-eucladian.js
new file mode 100644
index 000000000..927940fbc
--- /dev/null
+++ b/src/data-structures/array/gcd-eucladian.js
@@ -0,0 +1,7 @@
+function gcd(a, b) {
+  if (a === 0) return b;
+  let remainder = b % a;
+  return gcd(remainder, a);
+}
+
+console.log(gcd(22, 24));

From f245d5f8d0b09044cb1bec50de0fdc015e0871ba Mon Sep 17 00:00:00 2001
From: Rohit Dandnayak <rohit.dandnayak@ril.com>
Date: Thu, 18 Apr 2019 19:05:04 +0530
Subject: [PATCH 2/3] more alogs added

---
 src/data-structures/array/armstrong.js         | 13 +++++++++++++
 src/data-structures/array/array-rotation.js    |  2 +-
 src/data-structures/array/decimal-to-binary.js |  9 +++++++++
 src/data-structures/array/factorial.js         | 10 ++++++++++
 src/data-structures/array/fibonacci.js         | 15 +++++++++++++++
 src/data-structures/array/matching-socks.js    | 15 +++++++++++++++
 src/data-structures/array/palindrome.js        | 15 +++++++++++++++
 src/data-structures/array/prime-no.js          | 12 ++++++++++++
 src/data-structures/array/reverse-number.js    | 14 ++++++++++++++
 src/data-structures/array/sum-of-digits.js     | 13 +++++++++++++
 src/data-structures/array/swap-numbers.js      |  8 ++++++++
 11 files changed, 125 insertions(+), 1 deletion(-)
 create mode 100644 src/data-structures/array/armstrong.js
 create mode 100644 src/data-structures/array/decimal-to-binary.js
 create mode 100644 src/data-structures/array/factorial.js
 create mode 100644 src/data-structures/array/fibonacci.js
 create mode 100644 src/data-structures/array/matching-socks.js
 create mode 100644 src/data-structures/array/palindrome.js
 create mode 100644 src/data-structures/array/prime-no.js
 create mode 100644 src/data-structures/array/reverse-number.js
 create mode 100644 src/data-structures/array/sum-of-digits.js
 create mode 100644 src/data-structures/array/swap-numbers.js

diff --git a/src/data-structures/array/armstrong.js b/src/data-structures/array/armstrong.js
new file mode 100644
index 000000000..4b71a5a2d
--- /dev/null
+++ b/src/data-structures/array/armstrong.js
@@ -0,0 +1,13 @@
+function armstrong(n) {
+  let sum = 0,
+    num = n;
+  while (num > 0) {
+    rem = num % 10;
+    sum = sum + rem * rem * rem;
+    num = Math.trunc(num / 10);
+  }
+  if (sum === n) return 'armstrong';
+  else return 'not armstrong';
+}
+
+console.log(armstrong(153));
diff --git a/src/data-structures/array/array-rotation.js b/src/data-structures/array/array-rotation.js
index e42533e3a..2518cfa1c 100644
--- a/src/data-structures/array/array-rotation.js
+++ b/src/data-structures/array/array-rotation.js
@@ -15,4 +15,4 @@ function rotateArrayBy(arr, d) {
   return arr;
 }
 
-console.log(rotateArrayBy([1, 2, 3, 4, 5], 2));
+console.log(rotLeft([1, 2, 3, 4, 5], 3));
diff --git a/src/data-structures/array/decimal-to-binary.js b/src/data-structures/array/decimal-to-binary.js
new file mode 100644
index 000000000..563a188a1
--- /dev/null
+++ b/src/data-structures/array/decimal-to-binary.js
@@ -0,0 +1,9 @@
+function decimalToBinary(n) {
+  let a = [];
+  for (let i = 0; n > 0; i++) {
+    a[i] = n % 2;
+    n = Math.trunc(n / 2);
+  }
+  return a.reverse().join('');
+}
+console.log(decimalToBinary(8));
diff --git a/src/data-structures/array/factorial.js b/src/data-structures/array/factorial.js
new file mode 100644
index 000000000..7dddbf47f
--- /dev/null
+++ b/src/data-structures/array/factorial.js
@@ -0,0 +1,10 @@
+function factorial(n) {
+  let fact = n;
+  while (n > 1) {
+    fact = fact * (n - 1);
+    n = n - 1;
+  }
+  return fact;
+}
+
+console.log(factorial(5));
diff --git a/src/data-structures/array/fibonacci.js b/src/data-structures/array/fibonacci.js
new file mode 100644
index 000000000..6e5dd8e29
--- /dev/null
+++ b/src/data-structures/array/fibonacci.js
@@ -0,0 +1,15 @@
+function fibonacci(number) {
+  let n1 = 0,
+    n2 = 1,
+    n3;
+  console.log(n1);
+  console.log(n2);
+  for (let i = 2; i < number; ++i) {
+    n3 = n1 + n2;
+    console.log(n3);
+    n1 = n2;
+    n2 = n3;
+  }
+}
+
+console.log(fibonacci(9));
diff --git a/src/data-structures/array/matching-socks.js b/src/data-structures/array/matching-socks.js
new file mode 100644
index 000000000..07f5f8481
--- /dev/null
+++ b/src/data-structures/array/matching-socks.js
@@ -0,0 +1,15 @@
+let n = 9,
+  ar = [10, 20, 20, 10, 10, 30, 50, 10, 20];
+function sockMerchant(n, ar) {
+  let length = 0;
+  ar = ar.sort((a, b) => {
+    return a - b;
+  });
+  for (let i = 0; i < n; i++) {
+    if (ar.slice(i + 1, n).indexOf(ar[i]) > -1) {
+      length++, i++;
+    }
+  }
+  return length;
+}
+console.log(sockMerchant(n, ar));
diff --git a/src/data-structures/array/palindrome.js b/src/data-structures/array/palindrome.js
new file mode 100644
index 000000000..47bb35604
--- /dev/null
+++ b/src/data-structures/array/palindrome.js
@@ -0,0 +1,15 @@
+function isPalindrome(n) {
+  let revString = 0,
+    rem,
+    temp;
+  temp = n;
+  while (n > 0) {
+    rem = n % 10;
+    revString = revString * 10 + rem;
+    n = Math.trunc(n / 10);
+  }
+  if (temp !== revString) return 'not palindrome';
+  else return 'is palindrome';
+}
+
+console.log(isPalindrome(1231));
diff --git a/src/data-structures/array/prime-no.js b/src/data-structures/array/prime-no.js
new file mode 100644
index 000000000..38147f70c
--- /dev/null
+++ b/src/data-structures/array/prime-no.js
@@ -0,0 +1,12 @@
+function ifPrime(n) {
+  let flag = 0;
+  for (let i = 2; i < n; i++) {
+    if (n % i === 0) {
+      flag = 1;
+    }
+  }
+  if (flag == 0) return 'Is Prime';
+  else return 'not prime';
+}
+
+console.log(ifPrime(9));
diff --git a/src/data-structures/array/reverse-number.js b/src/data-structures/array/reverse-number.js
new file mode 100644
index 000000000..f2bf0c054
--- /dev/null
+++ b/src/data-structures/array/reverse-number.js
@@ -0,0 +1,14 @@
+function reverseNumber(num) {
+  var reverse = 0,
+    rem;
+  while (num !== 0) {
+    rem = num % 10;
+    // console.warn(num);
+    reverse = reverse * 10 + rem;
+    num = Math.trunc(num / 10);
+  }
+  return reverse;
+}
+
+// reverseNumber(123);
+console.log(reverseNumber(12345));
diff --git a/src/data-structures/array/sum-of-digits.js b/src/data-structures/array/sum-of-digits.js
new file mode 100644
index 000000000..1caffa6cd
--- /dev/null
+++ b/src/data-structures/array/sum-of-digits.js
@@ -0,0 +1,13 @@
+function sumOfDigits(num) {
+  var sum = 0,
+    rem;
+  while (num > 0) {
+    rem = num % 10;
+    sum = sum + rem;
+    num = Math.trunc(num / 10);
+  }
+  return sum;
+}
+
+// reverseNumber(123);
+console.log(sumOfDigits(126));
diff --git a/src/data-structures/array/swap-numbers.js b/src/data-structures/array/swap-numbers.js
new file mode 100644
index 000000000..b50d87dba
--- /dev/null
+++ b/src/data-structures/array/swap-numbers.js
@@ -0,0 +1,8 @@
+function swapNumbers(a, b) {
+  a = a + b;
+  b = a - b;
+  a = a - b;
+  return `${a}-${b}`;
+}
+
+console.log(swapNumbers(2, 5));

From f5d7715a7bee6d2a506230243727cf3da99ddaab Mon Sep 17 00:00:00 2001
From: Rohit Dandnayak <rohit.dandnayak@ril.com>
Date: Mon, 22 Apr 2019 14:31:14 +0530
Subject: [PATCH 3/3] array-rotation & nge

---
 src/data-structures/array/array-rotation.js | 26 ++++++++++++++++++++-
 src/data-structures/stack/nge.js            |  3 +++
 2 files changed, 28 insertions(+), 1 deletion(-)
 create mode 100644 src/data-structures/stack/nge.js

diff --git a/src/data-structures/array/array-rotation.js b/src/data-structures/array/array-rotation.js
index 2518cfa1c..9c2afef74 100644
--- a/src/data-structures/array/array-rotation.js
+++ b/src/data-structures/array/array-rotation.js
@@ -8,6 +8,29 @@ function rotateArray(arr) {
   return arr;
 }
 
+function gcd(a, b) {
+  if (a <= 0) return b;
+  let x = b - a;
+  return gcd(x, a);
+}
+
+function rotateJuggling(arr, d) {
+  let len = arr.length;
+  for (let i = 0; i < gcd(d, len); i++) {
+    let temp = arr[i];
+    let j = i;
+    while (1) {
+      let k = j + d;
+      if (k >= len) k = k - len;
+      if (k === i) break;
+      arr[j] = arr[k];
+      j = k;
+    }
+    arr[j] = temp;
+  }
+  return arr;
+}
+
 function rotateArrayBy(arr, d) {
   for (let i = 0; i < d; i++) {
     rotateArray(arr);
@@ -15,4 +38,5 @@ function rotateArrayBy(arr, d) {
   return arr;
 }
 
-console.log(rotLeft([1, 2, 3, 4, 5], 3));
+console.log(rotateArrayBy([1, 2, 3, 4, 5], 3));
+console.log(rotateJuggling([1, 2, 3, 4, 5], 3));
diff --git a/src/data-structures/stack/nge.js b/src/data-structures/stack/nge.js
new file mode 100644
index 000000000..0638d6272
--- /dev/null
+++ b/src/data-structures/stack/nge.js
@@ -0,0 +1,3 @@
+function printNGE(arr) {
+  for (let i, len = arr.length; i < len; i++) {}
+}