provided an integral number print all its factors which when multiplied gives the original number

Consider values for negative n

Implement pow(x, n), which calculates x raised to the power n (x^n).

Examples
Input: 2, -2
Output : 0.25

Input: 2.00000, 10
Output: 1024.00000

Push code to Math/Power/{ur file}

Given a binary matrix. The problem is to find the largest area rectangular sub-matrix with equal number of 1’s and 0’s.

Input : mat[][] = { {0, 0, 1, 1},
{0, 1, 1, 0},
{1, 1, 1, 0},
{1, 0, 0, 1} }
Output : 8 sq. units
(Top, left): (0, 0)
(Bottom, right): (3, 1)

Input : mat[][] = { {0, 0, 1, 1},
{0, 1, 1, 1} }
Output : 6 sq. units

Time Complexity : O(Row x Col)

Bubble Sort Algorithm in Java

Given an array of strings, group anagrams together.

Example
Input: ["eat", "tea", "tan", "ate", "nat", "bat"],
Output:
[
  ["ate","eat","tea"],
  ["nat","tan"],
  ["bat"]
]

Place code in String subfolder

• Edmond-Karp's

• Dinic's

Implement pow(x, n), which calculates x raised to the power n (x^n).

Examples
Input: 2.00000, 10
Output: 1024.00000

Consider negative exponents

A Hamiltonian cycle (or Hamiltonian circuit) is a Hamiltonian Path such that there is an edge (in graph) from the last vertex to the first vertex of the Hamiltonian Path.

Determine whether a given graph contains Hamiltonian Cycle or not. If it contains, then print the path. Following are the input and output of the required function.

Write a function that, for a given no n, finds a number p which is greater than or equal to n and is a smallest power of 2.

Input  : n = 17
Output : 32     

Input  : n = 32
Output : 32     

Write a function that calculates and returns log_2 n . For example, if n = 64, then your function should return 6

Given an expression string exp , write a program to examine whether the pairs and the orders of “{“,”}”,”(“,”)”,”[“,”]” are correct in exp. For example, the program should print true for exp = “[()]{}{()()}” and false for exp = “[(])”

Well i use this sites and files to learn more about Competitive Programming:

Introduction Books and ICPC documentation, also in spanish language:

-Training Camp
-Competitive Programming 3
-Algorithms

Some Online Judges:

-UVA Online Judge
-Codeforces
-Sphere Online Judge
-ACM ICPC Live Archive

Web Sites

-Geeks for Geeks
-Visualgo
-e-maxx-eng
-uDebug

Given an array of integers, find any one combination of four elements in the array whose sum is equal to a given value X.
For example, if the given array is {10, 2, 3, 4, 5, 9, 7, 8} and X = 23, then your function should print “3 5 7 8” (3 + 5 + 7 + 8 = 23).

Put code in Hashing

Given two arrays, find length of the longest common increasing subsequence [LCIS] and print one of such sequences (multiple sequences may exist)

Suppose we consider two arrays –
arr1[] = {3, 4, 9, 1} and
arr2[] = {5, 3, 8, 9, 10, 2, 1}

The answer would be {3, 9} as this is the longest common subsequence which is increasing also.

Give instructions how to follow the file structure and create a pull request

longest increasing subsequence

The Longest Increasing Subsequence (LIS) problem is to find the length of the longest subsequence of a given sequence such that all elements of the subsequence are sorted in increasing order. For example, the length of LIS for {10, 22, 9, 33, 21, 50, 41, 60, 80} is 6 and LIS is {10, 22, 33, 50, 60, 80}.

Given an array and a value, find if there is a triplet in array whose sum is equal to the given value. If there is such a triplet present in array, then print the triplet and return true. Else return false. For example, if the given array is {12, 3, 4, 1, 6, 9} and given sum is 24, then there is a triplet (12, 3 and 9) present in array whose sum is 24.

You can follow this solution in C++, using HashMap to get O(n) solution.

`#include < map >

using namespace std;

class Solution {
public:
vector twoSum(vector &numbers, int target) {
int len = numbers.size();
map<int, int> r;
vector rr;
for (int i = 0; i < len; i ++) {
if (r.find(numbers[i]) == r.end()) { // if not exist
r[numbers[i]] = i; // add it to the map
}
int j, num = target - numbers[i];
if ((r.find(num) != r.end()) && ((j = r[num]) < i)) {
rr.push_back(j + 1);
rr.push_back(i + 1);
return rr;
}
}
return rr;
}
};`

• - Dijkstra

• - Kruskal

• - Prims

• - Topological Sort

• - Floyd Warshall

• - Dial’s

• - Johnson’s

• - Tarjan’s

Given an array of numbers. Find longest increasing subsequence (LIS) in the array.

Example { 2, 5, 3, 7, 11, 8, 10, 13, 6 }
Length of Longest Increasing Subsequence is 6

Time Complexity:
O(N log N)

Additional resources:
https://www.youtube.com/watch?v=S9oUiVYEq7E

Implement int sqrt(int x).

Compute and return the square root of x, where x is guaranteed to be a non-negative integer.

Since the return type is an integer, the decimal digits are truncated and only the integer part of the result is returned.

Given an integer x, find square root of it. If x is not a perfect square, then return floor(√x).

Examples:
Input: x = 4
Output: 2

Input: x = 11
Output: 3

Subset Sum Problem

Given a set of non-negative integers, and a value sum, determine if there is a subset of the given set with sum equal to given sum.

Examples: set[] = {3, 34, 4, 12, 5, 2}, sum = 9
Output: True //There is a subset (4, 5) with sum 9.

Find the largest rectangular area possible in a given histogram

where the largest rectangle can be made of a number of contiguous bars. For simplicity, assume that all bars have same width and the width is 1 unit.

For example, consider the following histogram with 7 bars of heights {6, 2, 5, 4, 5, 1, 6}. The largest possible rectangle possible is 12 (see the below figure, the max area rectangle is highlighted in red)

Given an array and a value, find if there is a triplet in array whose sum is equal to the given value. If there is such a triplet present in array, then print the triplet and return true. Else return false. For example, if the given array is {12, 3, 4, 1, 6, 9} and given sum is 24, then there is a triplet (12, 3 and 9) present in array whose sum is 24.

Put the code in Hashing/3_Sum/{ur file}

please write a gitignore that at least considers for .pyc and a.out and others

The problem is to count all the possible paths from top left to bottom right of a mXm matrix with the constraints that from each cell you can either move only to right or down

Example

Starting in the top left corner of a 2×2 grid, and only being able to move to the right and down, there are exactly 6 routes to the bottom right corner.

Given a non-empty list of words, return the k most frequent elements.

Your answer should be sorted by frequency from highest to lowest. If two words have the same frequency, then the word with the lower alphabetical order comes first.

Example 1: Input: ["i", "love", "leetcode", "i", "love", "coding"], k = 2 Output: ["i", "love"] Explanation: "i" and "love" are the two most frequent words. Note that "i" comes before "love" due to a lower alphabetical order.

Example 2: Input: ["the", "day", "is", "sunny", "the", "the", "the", "sunny", "is", "is"], k = 4 Output: ["the", "is", "sunny", "day"] Explanation: "the", "is", "sunny" and "day" are the four most frequent words, with the number of occurrence being 4, 3, 2 and 1 respectively.

greedy seems to be a concept, sorting algorithms into their usage should be better 😄

Coin change

Given a value V, if we want to make change for V cents, and we have infinite supply of each of C = { C1, C2, .. , Cm} valued coins, what is the minimum number of coins to make the change?
Input: coins[] = {25, 10, 5}, V = 30
Output: Minimum 2 coins required
We can use one coin of 25 cents and one of 5 cents

Input: coins[] = {9, 6, 5, 1}, V = 11
Output: Minimum 2 coins required
We can use one coin of 6 cents and 1 coin of 5 cents

Maximum size square sub-matrix with all 1s

Given a binary matrix, find out the maximum size square sub-matrix with all 1s.

Edit Distance

Given two strings str1 and str2 and below operations that can performed on str1. Find minimum number of edits (operations) required to convert ‘str1’ into ‘str2’.

Insert
Remove
Replace
All of the above operations are of equal cost.

Input: str1 = "geek", str2 = "gesek"
Output: 1
We can convert str1 into str2 by inserting a 's'.

Input: str1 = "cat", str2 = "cut"
Output: 1
We can convert str1 into str2 by replacing 'a' with 'u'.

Input: str1 = "sunday", str2 = "saturday"
Output: 3
Last three and first characters are same. We basically
need to convert "un" to "atur". This can be done using
below three operations.
Replace 'n' with 'r', insert t, insert a

Given two strings S and T, find length of the shortest subsequence in S which is not a subsequence in T. If no such subsequence is possible, return -1. A subsequence is a sequence that appears in the same relative order, but not necessarily contiguous. A string of length n has 2^n different possible subsequences.

Input : S = “babab” T = “babba”
Output : 3
The subsequence “aab” of length 3 is
present in S but not in T.

Input : S = “abb” T = “abab”
Output : -1
There is no subsequence that is present
in S but not in T.

Algorithm should have
Time complexity : O(mn^2)
Space Complexity : O(mn)

one of the basic dp problem is maximum sum increasing subsequence it will be good to include this

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

Example:

Given nums = [2, 7, 11, 15], target = 9,

Because nums[0] + nums[1] = 2 + 7 = 9,
return [0, 1].

Selection of Random Number from stream of numbers

Given a number x, find sum of digits in all numbers from 1 to n.

Input: n = 5
Output: Sum of digits in numbers from 1 to 5 = 15

Input: n = 12
Output: Sum of digits in numbers from 1 to 12 = 51

Input: n = 328
Output: Sum of digits in numbers from 1 to 328 = 3241