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Author: codermehraj

LICENSE

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+MIT License
+
+Copyright (c) 2020 Define Coder
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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-# definecoder.github.io
-ONE PLACE TO RULE THEM ALL
+# Welcome to DefineCoder
+
+## Click the following links to see my notes on that topic
+
+- [Sandard Template Library ~ STL](https://definecoder.github.io/STL/home)
+- Graph Theory
+  - BFS
+  - DFS
+  - Dijkstra
+- Dynamic Programming
+- BitSet
+- Greedy
+- Two Pointer
+- Geometry
+- Combinatorics
+
+## This page is managed by :
+- [Md. Mehrajul Islam](https://codermehraj.github.io) 
+- [Ariful Islam Shanto](https://shanto-swe029.github.io)
+- [Shawon Majid](https://shawon-majid.github.io)
+- [Samiul Islam Mugdha](https://mugdha-samiul.github.io)

STL/home.md

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+# Standard Template Library in C++
+
+STL is a very powefull tool for **competitive programming**. It saves a lot of time and makes your code easier to read.  
+<br>
+## I will talk about these in this note :
+`Click in the links to see the notes on that topic`
+- [String](https://definecoder.github.io/STL/string)
+- [Pair](https://definecoder.github.io/STL/pair)
+- [Vector](https://definecoder.github.io/STL/vector)
+- [Stack](https://definecoder.github.io/STL/stack)
+- Queue
+  * Deque
+- Priority Queue
+- Set
+  * Multiset
+  * Unordered Set
+  * Unordered Multiset
+- Map
+  * Multimap
+  * Unordered Map
+  * Unordered Multimap
+- List
+<br>
+Also some useful features like `next_permutaion() , stringstream` etc in this **link**

STL/pair.md

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+# Let's Make some Pairs!

STL/stack.md

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+# stack
+tutorial about stack

STL/string.md

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+
+# String
+
+To use string first of all you have to add this header **` #include <string> `**
+
+## Declaring and Initializing a String 
+It is very easy to declare a string. You can create a string variable nammed as MyString by typing **` string MyString ; `**
+
+You can declare several string togather in a line. You can also _**initialize**_ a string using **` string MyString = "Hello World!" `**. 
+You can also do that later in your code.
+
+You can take a string from the user using **` cin >> MySting ; `** which only takes the string _**up to a space**_
+
+If you want to get _**a full line including spaces**_ use this instead  **` getline( cin , MyString ) ; `**
+
+## Basic Sting Operations
+
+Lets say you have two strings **` string a = "Hello " , b = "World" ; `** You can add string **b** after string **a** using **` a = a + b `**
+after this opatertion the value of a will be **"Hello World"**. 
+That is how you can **concatenate** two strings.
+
+You can delete last charecter on a sting using **` MyString.pop_back() `**
+
+As you know string is an array of charecters so you can access any index (0 to length-1) and change that in constant time. _e.g:_ **` MyString[0] = 'h' ; `**
+
+You can print a string using **` cout << MyString << endl ; `**
+
+You can check the equality of two strings using  **` strA == strB `** and inequality using **` strA != strB `** . 
+You can also check which string is lexicographically greater using **` strA > strB `** vice versa.
+
+## String Functions :
+
+|         Function        |                              Work of the function                              |
+|:-----------------------:|:------------------------------------------------------------------------------:|
+|     MyString.size()     |                         Returns The size of the string                         |
+|     str1.swap(str2)     |                        Swaps the value of str1 and str2                        |
+|   MyString.insert(x,s)  |                     Inserts s in the xth index of MyString                     |
+|     MySrting.find(s)    | returns initial index of first occurrence of the s in MyString else returns -1 |
+|    MySrting.rfind(s)    |  returns initial index of last occurrence of the s in MyString else returns -1 |
+| MyString.replace(i,j,s) |       Replaces j characters from ith index of MyString with new string s       |
+|      stoi(MyString)     |                 Returns the integer converted form of MyString                 |
+|   MyString.substr(i,k)  |            Returns a substing of length k from ith index of MyString           |
+|    MyString.erase(i)    |           Erases every element from ith index to the end of MyString           |
+|     MyString.clear()    |                        Erases every element in MyStirng                        |
+|     MyString.empty()    |              Returns True if  MyString is empty else return false              |

STL/vector.md

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+# Vector
+## Introduction
+Vector is one of the most powerful Data Type in ***C++ programming language*** and very much helpful for competitive programmers. The concept of vector is almost same as C programming language’s ***Array***. However, in C++, we call the vector ***“A Container”***. A container can contain everything such as *<ins>`integers, doubles, characters, bools, strings, structures`</inS>* and a vector can contain *<ins>`some vectors`</ins>* too. But the most important feature of vector is –***“Its memory is allocated dynamically.”*** We can change its length at any time and you can perform many operations that is not possible for C language’s array. We will see and learn all of these things gradually in a proper way.
+<br/>
+<br/>
+## Header File
+We have to include an extra header file to use this data type. That is- <br/>
+`#include <vector>`<br/>
+Under this header file, we can access all the library functions that can be used for vector data type.
+<br/>
+<br/>
+## Declaration and initialization of a vector
+We can declare a vector in several ways. Let us see them one by one and understand their differences gradually.
+  - `vector < Datatype > MyVector;`<br/>
+Using this format, we can declare a vector. Now we can see that the size of the vector is not mentioned here. That means **“we have not allocated any memory for this vector.”** In this case if we want to add any value (of the datatype mentioned inside), we have to use a library function `push_back()`. For example, if we want to store 55, 72, 89 and 100 into an integer vector, we have to perform these:
+```
+    vector < int > v;
+    v.push_back(55);
+    v.push_back(72);
+    v.push_back(89);
+    v.push_back(100);
+```
+Alternatively, we can write them also in a single line using commas, like this-
+```
+    vector < int > v;
+    v.push_back(55), v.push_back(72), v.push_back(89), v.push_back(100);
+```
+The size of vector  `v` will be as much element we insert into the vector using `push_back()` function. 
+  - `vector < Datatype > MyVector(n);`     where n = size of the vector.<br/>
+Thus we can initially allocate the memory needed for our vector like this. Using this method will give us two extra benefit:
+    - This will set the values of all index to 0 automatically.
+    - We can now access any index form 0 to size-1 inclusively by <br/>`“MyVector[i]”`; where i = index.<br/>
+But still we can change the size of the vector at any time. Besides, we can also store more than n elements into the vector (if needed). Using `push_back()`, we can add elements from index n to maximum size.
+
+Suppose, we are declaring a vector of length 3 and store 3 values into the vector. we have to do it like-
+```
+    vector < int > v(3);
+    v[0] = 29, v[1] = 37, v[2] = 23;
+```
+
+Now if we want to add more elements, we can do it by simply using `push_back()`. <br/>
+```
+    v.push_back(18), v.push_back(97);
+```
+**Now the size of the vector is increased from three to five**.

_config.yml

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+theme: jekyll-theme-cayman