Suppose we have an integer; we have to devise an algorithm to convert it to hexadecimal. For negative numbers we will use the two’s complement method.So, if the input is like 254 and -12, then the output will be fe and fffffff4 respectively.To solve this, we will follow these steps −if num1 is same as 0, then −return "0"num := num1s := blank stringwhile num is non-zero, do −temp := num mod 16if temp

Suppose we have two strings s and t which consist of only lowercase letters. Now, string t is generated by random shuffling string s and then add one more letter at a random index. We have to find the letter that was added in t.So, if the input is like "mnopq", "pqmnot", then the output will be "t", this is the extra letter.To solve this, we will follow these steps −sSum := 0, tSum := 0for initialize i := 0, when i < call length() of s, update (increase i by 1), do −sSum := sSum + s[i]for initialize j ... Read More

Suppose we are playing the Guess Game. The properties of this game is as follows −Player 1 will pick a number from 1 to n. player2 have to guess which number I picked. Every time player2 guess wrong, player1 will tell player2 whether the number is higher or lower.We can use the function guess(num) which will return 3 possible results as follows −-1 − Player1's number is lower1 − Player1's number is higher0 − Number is matchedSo, if the input is like n = 10, pick = 5, then the output will be 5.To solve this, we will follow these ... Read More

Suppose we have two arrays; we have to find their intersections.So, if the input is like [1, 5, 3, 6, 9], [2, 8, 9, 6, 7], then the output will be [9, 6]To solve this, we will follow these steps −Define two maps mp1, mp2Define an array resfor x in nums1(increase mp1[x] by 1)for x in nums2(increase mp2[x] by 1)for each key-value pair x in mp1cnt := 0cnt := minimum of value of x and mp2[key of x]if cnt > 0, then −insert key of x at the end of resreturn resExample Let us see the following implementation to get a ... Read More

Suppose we have an integer; we have to check whether that is a power of 4 or not.So, if the input is like 16, then the output will be True.To solve this, we will follow these steps −if num < 0, then −return falseif num & (num - 1) is non-zero, then −return falseif (num & 01010101010101010101010101010101) is zero, then −return falsereturn trueExample Let us see the following implementation to get better understanding − Live Demo#include using namespace std; class Solution { public:    bool isPowerOfFour(int num){       if (num < 0)          return false;   ... Read More

Suppose we are playing a game called, Nim Game with another player. There is a heap of stones, each time one player takes turns to remove 1 to 3 stones. The one who removes the last stone will be the winner. Player1 will take the first turn to remove the stones. Both of the players are very clever and have optimal strategies for the game. We have to devise an algorithm to determine whether player1 can win the game given the number of stones in the heap.So, if the input is like 5, then the output will be true, as ... Read More

Suppose we have a pattern and a string str, find if str follows the same pattern. Here follow means there is a bijection between a letter in pattern and a non-empty word in str.So, if the input is like pattern = "cbbc", str = "word pattern pattern word", then the output will be True.To solve this, we will follow these steps −strcin := strDefine an array of wordsfor each word in strcininsert word at the end of wordsDefine one map p2ii := 0pat := empty stringfor c in pattern −if c is not member of p2i, then −(increase i by ... Read More

Suppose we want to implement one stack using a queue. We have to define these methods for the stack.push(x) − Push x onto stack.pop() − Delete and return top element from stacktop() − Return the top element from stack.empty() − Return whether the stack is empty or not.So, if we call the functions push(10), push(20), then call pop(), pop(), then the output will be 20, 10To solve this, we will follow these steps −Define one deque qDefine a function push(), this will take x, insert x at the beginning of qDefine a function pop()k := first element of qdelete front ... Read More

Suppose we have an array and an integer k, we have to check whether there are two distinct indices i and j in the array such that nums[i] = nums[j] and the absolute difference between i and j is at most k.So, if the input is like [1, 2, 4, 1] and k = 3, then the output will be TrueTo solve this, we will follow these steps −Define an array nn of pairsfor initialize i := 0, when i − size of nums, update (increase i by 1), do −insert {nums[i], i} at the end of nnsort the array ... Read More

Suppose we have two strings s and t; we have to check whether they are isomorphic or not. Two strings are said to be isomorphic if the characters in s can be replaced to get t.All occurrences of a character must be replaced with another character while preserving the order of characters. No two characters may map to the same character but a character may map to itself.So, if the input is like s = "egg", t = "add”, then the output will be true, as e can map to a, and g can map to d.To solve this, we ... Read More