From 9b8440949b10076f0c207d6ff82ddb274c7b39c0 Mon Sep 17 00:00:00 2001
From: Nithin Mahendran <nithinmahendren@gmail.com>
Date: Tue, 5 Oct 2021 00:35:06 +0530
Subject: [PATCH] Instagram bug fix

---
 .../{ => Stack using Array}/README.MD         |  20 +-
 ...enting_stack_using_array_and_linked_list.c | 436 +++++++++---------
 .../Two Sum Problem/two_sum.py                |  13 +
 program-72/program.c                          |  52 ---
 program-72/readme.md                          |   3 -
 5 files changed, 241 insertions(+), 283 deletions(-)
 rename Interview Questions/{ => Stack using Array}/README.MD (97%)
 rename Interview Questions/{ => Stack using Array}/implementing_stack_using_array_and_linked_list.c (95%)
 create mode 100644 Interview Questions/Two Sum Problem/two_sum.py
 delete mode 100644 program-72/program.c
 delete mode 100644 program-72/readme.md

diff --git a/Interview Questions/README.MD b/Interview Questions/Stack using Array/README.MD
similarity index 97%
rename from Interview Questions/README.MD
rename to Interview Questions/Stack using Array/README.MD
index 65b6f3b6..02569009 100644
--- a/Interview Questions/README.MD	
+++ b/Interview Questions/Stack using Array/README.MD	
@@ -1,10 +1,10 @@
-# Interview Questions and Answers
-
-| Sl no. | Question | Answer link | Language | Contributor |
-|---|---|---|---|---|
-| 1 | Implementing **Stack** using **Array** and **Linked List** | [code here](https://github.com/nitinkumar30/basicprograms/blob/master/Interview%20Questions/implementing_stack_using_array_and_linked_list.c) | C | [Nitin Kumar](https://github.com/nitinkumar30/)
-
-
-# Repo contributed by
-
-[Nitin Kumar](https://github.com/nitinkumar30/)
+# Interview Questions and Answers
+
+| Sl no. | Question | Answer link | Language | Contributor |
+|---|---|---|---|---|
+| 1 | Implementing **Stack** using **Array** and **Linked List** | [code here](https://github.com/nitinkumar30/basicprograms/blob/master/Interview%20Questions/implementing_stack_using_array_and_linked_list.c) | C | [Nitin Kumar](https://github.com/nitinkumar30/)
+
+
+# Repo contributed by
+
+[Nitin Kumar](https://github.com/nitinkumar30/)
diff --git a/Interview Questions/implementing_stack_using_array_and_linked_list.c b/Interview Questions/Stack using Array/implementing_stack_using_array_and_linked_list.c
similarity index 95%
rename from Interview Questions/implementing_stack_using_array_and_linked_list.c
rename to Interview Questions/Stack using Array/implementing_stack_using_array_and_linked_list.c
index e103e454..772ec406 100644
--- a/Interview Questions/implementing_stack_using_array_and_linked_list.c	
+++ b/Interview Questions/Stack using Array/implementing_stack_using_array_and_linked_list.c	
@@ -1,218 +1,218 @@
-// Implementing stack using Array in C language
-
-// -------------------------------------------------------
-
-#include<stdio.h>
-#include<stdlib.h>
-
-struct Stack{
-    int size;
-    int top;
-    int *arr;
-};
-
-// ---- operations to perform :
-// isEmpty-
-// isFull-
-// push-
-// pop-
-// peek-
-// stackTop-
-// stackBottom-
-
-// -------------------------------------
-
-int isEmpty(struct Stack * ptr){
-    if(ptr->top == -1)
-        return 1;
-    else
-        return 0;
-}
-// -------------------------------------
-
-int isFull(struct Stack * ptr){
-    if(ptr->top == ptr->size-1)
-        return 1;
-    else
-        return 0;
-}
-// -------------------------------------
-
-void push(struct Stack *ptr, int data){
-    if(isFull(ptr)){
-        printf("Stack Overflow for data %d \n", data);
-    }
-    else{
-        ptr->top+=1;
-        ptr->arr[ptr->top] = data;
-    }
-}
-// -------------------------------------
-
-int pop(struct Stack *ptr){
-    if(isEmpty(ptr))
-        printf("Stack Underflow");
-    else{
-        int p = ptr->arr[ptr->top];
-        ptr->top-=1;
-        return p;
-    }
-}
-// -------------------------------------
-
-int peek(struct Stack *ptr, int i){
-    int arrInd = ptr->top-i+1;
-    if(arrInd <= -1)
-        printf("Not valid position.");
-    else
-        return ptr->arr[arrInd];
-    return -1;
-}
-// -------------------------------------
-
-int stackTop(struct Stack *ptr){
-    return ptr->arr[ptr->top];
-}
-// -------------------------------------
-
-int stackBottom(struct Stack *ptr){
-    return ptr->arr[0];
-}
-// -------------------------------------
-
-int main(){
-    struct Stack *s = (struct Stack *)malloc(sizeof(struct Stack));
-    s->size=10;
-    s->top=-1;
-    s->arr=(int *)malloc(s->size*sizeof(int));
-    
-    printf("Before pushing: Full %d\n",isFull(s));
-    printf("Before pushing: Empty %d\n",isEmpty(s));
-    
-    push(s, 1);
-    push(s, 2);
-    push(s, 3);
-    push(s, 4);
-    push(s, 5);
-    push(s, 6);
-    push(s, 7);
-    push(s, 8);
-    push(s, 9);
-    push(s, 10);
-    push(s, 11);
-    push(s, 12);
-    push(s, 13);
-    
-    printf("After pushing: Full %d\n",isFull(s));
-    printf("After pushing: Empty %d\n",isEmpty(s));
-    
-    printf("\n----------------------\n");
-    printf("Peeking through stack\n");
-    for(int j=1;j<s->top+2;j++){
-        printf("The value at position %d is %d\n", j, peek(s, j));
-    }
-    
-    printf("\nPopped %d from stack", pop(s));
-    printf("\nPopped %d from stack", pop(s));
-    printf("\nPopped %d from stack", pop(s));
-    printf("\nPopped %d from stack\n\n", pop(s));
-    
-    printf("After popping: Full %d\n",isFull(s));
-    printf("After popping: Empty %d\n",isEmpty(s));
-    
-    printf("\n----------------------\n");
-    printf("Peeking through stack\n");
-    for(int j=1;j<s->top+2;j++){
-        printf("The value at position %d is %d\n", j, peek(s, j));
-    }
-    
-    printf("\nStack at top now is %d", stackTop(s));
-    printf("\nStack at bottom now is %d", stackBottom(s));
-    
-    return 0;
-}
-
-// ------------------------------------------------------------------------------------------------------
-
-// Implementing Stack using Linked List in C language
-
-#include<stdio.h>
-#include<stdlib.h>
-
-struct Node{
-    int data;
-    struct Node *next;
-};
-
-// isEmpty
-// isFull
-// push
-// pop
-
-struct Node * top = NULL;
-
-void traverseLinkedList(struct Node *ptr){
-    while(ptr!=NULL){
-        printf("Element is %d\n", ptr->data);
-        ptr=ptr->next;
-    }
-}
-
-int isEmpty(struct Node *top){
-    if(top == NULL)
-        return 1;
-    else
-        return 0;
-}
-
-int isFull(struct Node *top){
-    struct Node *n = (struct Node*)malloc(sizeof(struct Node));
-    if (n==NULL)
-        return 1;
-    else
-        return 0;
-}
-
-int pop(struct Node *tp){
-    if(isEmpty(top))
-        printf("Stack Underflow");
-    else{
-        struct Node *p = tp;
-        top = (tp) -> next;
-        int m=p->data;
-        free(p);
-        return m;
-    }
-}
-
-struct Node *push(struct Node *top, int x){
-    if (isFull(top))
-        return 1;
-    else{
-        struct Node *pr = (struct Node*)malloc(sizeof(struct Node));
-        pr->data = x;
-        pr->next = top;
-        top = pr;
-        return top;
-    }
-}
-
-int main(){
-    top = push(top, 3);
-    top = push(top, 6);
-    top = push(top, 11);
-    top = push(top, 23);
-    top = push(top, 47);
-    
-    traverseLinkedList(top);
-    
-    int element=pop(top);
-    printf("Popped element is %d \n", element);
-    
-    traverseLinkedList(top);
-    
-    return 0;
-    
-}
-
-
+// Implementing stack using Array in C language
+
+// -------------------------------------------------------
+
+#include<stdio.h>
+#include<stdlib.h>
+
+struct Stack{
+    int size;
+    int top;
+    int *arr;
+};
+
+// ---- operations to perform :
+// isEmpty-
+// isFull-
+// push-
+// pop-
+// peek-
+// stackTop-
+// stackBottom-
+
+// -------------------------------------
+
+int isEmpty(struct Stack * ptr){
+    if(ptr->top == -1)
+        return 1;
+    else
+        return 0;
+}
+// -------------------------------------
+
+int isFull(struct Stack * ptr){
+    if(ptr->top == ptr->size-1)
+        return 1;
+    else
+        return 0;
+}
+// -------------------------------------
+
+void push(struct Stack *ptr, int data){
+    if(isFull(ptr)){
+        printf("Stack Overflow for data %d \n", data);
+    }
+    else{
+        ptr->top+=1;
+        ptr->arr[ptr->top] = data;
+    }
+}
+// -------------------------------------
+
+int pop(struct Stack *ptr){
+    if(isEmpty(ptr))
+        printf("Stack Underflow");
+    else{
+        int p = ptr->arr[ptr->top];
+        ptr->top-=1;
+        return p;
+    }
+}
+// -------------------------------------
+
+int peek(struct Stack *ptr, int i){
+    int arrInd = ptr->top-i+1;
+    if(arrInd <= -1)
+        printf("Not valid position.");
+    else
+        return ptr->arr[arrInd];
+    return -1;
+}
+// -------------------------------------
+
+int stackTop(struct Stack *ptr){
+    return ptr->arr[ptr->top];
+}
+// -------------------------------------
+
+int stackBottom(struct Stack *ptr){
+    return ptr->arr[0];
+}
+// -------------------------------------
+
+int main(){
+    struct Stack *s = (struct Stack *)malloc(sizeof(struct Stack));
+    s->size=10;
+    s->top=-1;
+    s->arr=(int *)malloc(s->size*sizeof(int));
+    
+    printf("Before pushing: Full %d\n",isFull(s));
+    printf("Before pushing: Empty %d\n",isEmpty(s));
+    
+    push(s, 1);
+    push(s, 2);
+    push(s, 3);
+    push(s, 4);
+    push(s, 5);
+    push(s, 6);
+    push(s, 7);
+    push(s, 8);
+    push(s, 9);
+    push(s, 10);
+    push(s, 11);
+    push(s, 12);
+    push(s, 13);
+    
+    printf("After pushing: Full %d\n",isFull(s));
+    printf("After pushing: Empty %d\n",isEmpty(s));
+    
+    printf("\n----------------------\n");
+    printf("Peeking through stack\n");
+    for(int j=1;j<s->top+2;j++){
+        printf("The value at position %d is %d\n", j, peek(s, j));
+    }
+    
+    printf("\nPopped %d from stack", pop(s));
+    printf("\nPopped %d from stack", pop(s));
+    printf("\nPopped %d from stack", pop(s));
+    printf("\nPopped %d from stack\n\n", pop(s));
+    
+    printf("After popping: Full %d\n",isFull(s));
+    printf("After popping: Empty %d\n",isEmpty(s));
+    
+    printf("\n----------------------\n");
+    printf("Peeking through stack\n");
+    for(int j=1;j<s->top+2;j++){
+        printf("The value at position %d is %d\n", j, peek(s, j));
+    }
+    
+    printf("\nStack at top now is %d", stackTop(s));
+    printf("\nStack at bottom now is %d", stackBottom(s));
+    
+    return 0;
+}
+
+// ------------------------------------------------------------------------------------------------------
+
+// Implementing Stack using Linked List in C language
+
+#include<stdio.h>
+#include<stdlib.h>
+
+struct Node{
+    int data;
+    struct Node *next;
+};
+
+// isEmpty
+// isFull
+// push
+// pop
+
+struct Node * top = NULL;
+
+void traverseLinkedList(struct Node *ptr){
+    while(ptr!=NULL){
+        printf("Element is %d\n", ptr->data);
+        ptr=ptr->next;
+    }
+}
+
+int isEmpty(struct Node *top){
+    if(top == NULL)
+        return 1;
+    else
+        return 0;
+}
+
+int isFull(struct Node *top){
+    struct Node *n = (struct Node*)malloc(sizeof(struct Node));
+    if (n==NULL)
+        return 1;
+    else
+        return 0;
+}
+
+int pop(struct Node *tp){
+    if(isEmpty(top))
+        printf("Stack Underflow");
+    else{
+        struct Node *p = tp;
+        top = (tp) -> next;
+        int m=p->data;
+        free(p);
+        return m;
+    }
+}
+
+struct Node *push(struct Node *top, int x){
+    if (isFull(top))
+        return 1;
+    else{
+        struct Node *pr = (struct Node*)malloc(sizeof(struct Node));
+        pr->data = x;
+        pr->next = top;
+        top = pr;
+        return top;
+    }
+}
+
+int main(){
+    top = push(top, 3);
+    top = push(top, 6);
+    top = push(top, 11);
+    top = push(top, 23);
+    top = push(top, 47);
+    
+    traverseLinkedList(top);
+    
+    int element=pop(top);
+    printf("Popped element is %d \n", element);
+    
+    traverseLinkedList(top);
+    
+    return 0;
+    
+}
+
+
diff --git a/Interview Questions/Two Sum Problem/two_sum.py b/Interview Questions/Two Sum Problem/two_sum.py
new file mode 100644
index 00000000..7802dc8c
--- /dev/null
+++ b/Interview Questions/Two Sum Problem/two_sum.py	
@@ -0,0 +1,13 @@
+def twoSum(self, nums: List[int], target: int) -> List[int]:
+
+    m = {} # store compliment and index of other value
+    
+    for i in range(len(nums)):
+        n = nums[i]
+        c = target - n
+        
+        if n in m:
+            i1 = m[n]
+            return [i1, i]
+        else:
+            m[c] = i
\ No newline at end of file
diff --git a/program-72/program.c b/program-72/program.c
deleted file mode 100644
index e5d23b81..00000000
--- a/program-72/program.c
+++ /dev/null
@@ -1,52 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-struct Node
-{
- int data;
- struct Node *next;
-}*first=NULL;
-void create(int A[],int n)
-{
- int i;
- struct Node *t,*last;
- first=(struct Node *)malloc(sizeof(struct Node));
- first->data=A[0];
- first->next=NULL;
- last=first;
- 
- for(i=1;i<n;i++)
- {
- t=(struct Node*)malloc(sizeof(struct Node));
- t->data=A[i];
- t->next=NULL;
- last->next=t;
- last=t;
- }
-}
-void Display(struct Node *p)
-{
- while(p!=NULL)
- {
- printf("%d ",p->data);
- p=p->next;
- }
-}
-void RDisplay(struct Node *p)
-{
- if(p!=NULL)
- {
- RDisplay(p->next);
- printf("%d ",p->data);
- 
- }
-}
-int main()
-{
- struct Node *temp;
- int A[]={3,5,7,10,25,8,32,2};
- create(A,8);
- 
- Display(first);
- 
- return 0;
-}
\ No newline at end of file
diff --git a/program-72/readme.md b/program-72/readme.md
deleted file mode 100644
index 3f17c521..00000000
--- a/program-72/readme.md
+++ /dev/null
@@ -1,3 +0,0 @@
-program 72
-
-C program to create and display a linked-lists
\ No newline at end of file