In this problem, we are given a matrix mat[][]. It defines a path with landmines which are marked as 0. Our task is to Find shortest safe route in a path with landmines.While traversing through the safe path, we need to avoid walking adjacent cells of the landmine (left, right, above and bottom) for being unsafe.All valid moves while traversing the path are −- Left : mat[i][j] => mat[i-1][j] - Right : mat[i][j] => mat[i+1][j] - Top : mat[i][j] => mat[i][j - 1] - Bottom : mat[i][j] => mat[i][j + 1]Let’s take an example to understand the problem, Inputmat[][] = ... Read More

In this problem, we are given a matrix mat[][] of size N*N. Our task is to Find the row with maximum sum in a Matrix.Let’s take an example to understand the problem, Inputmat[][] = {    8, 4, 1, 9    3, 5, 7, 9    2, 4, 6, 8    1, 2, 3, 4 }OutputRow 2, sum 24ExplanationRow 1: sum = 8+4+1+9 = 22 Row 2: sum = 3+5+7+9 = 24 Row 3: sum = 2+4+6+8 = 20 Row 4: sum = 1+2+3+4 = 10Solution ApproachA simple solution to the problem is to find the sum of elements of ... Read More

In this problem, we are given a binary matrix in which each row is sorted. Our task is to Find row number of a binary matrix having the maximum number of 1s.Let’s take an example to understand the problem, InputbinMat[][] = {    1, 1, 1, 1    0, 0, 0, 0    0, 0, 0, 1    0, 0, 1, 1 }Output1Solution ApproachA simple solution to the problem is to count the total number of 1’s in each row. And then return the row number with maximum 1 count.Program to illustrate the working of our solution, Example Live Demo#include ... Read More

In this problem we are given a binary tree and parent pointers. Our task is to Find right sibling of a binary tree with parent pointers.Let’s take an example to understand the problem, InputNode = 3Output7Solution ApproachA simple solution to the problem is finding the leaf node of the nearest ancestor (which is neither the current node nor the parest of the current node) which is at the same level as the current node. This is done by counting the levels while going up and then when coming down counting them down. And then finding the node.Program to illustrate the ... Read More

In this problem we are given five values m, n, mth term, nth term, p. Our task is to Find Pth term of a GP if Mth and Nth terms are given.For a GP, we are given the values of mth term and nth term. Using these values, we need to find the Pth term of the series.Let’s take an example to understand the problem, Inputm = 7, mthTerm = 1458, n = 10, nthterm = 39366, p = 3Output18Solution ApproachHere, we are given a GP. let's suppose the GP is, GP = a , a*r , a*(r2), a*(r3) ….The ... Read More

In this problem we are given four values p, q, r, s. Our task is to Find probability that a player wins when probabilities of hitting the target are given.Here, we have two players who are playing a game of archery. And the probability of player 1 hitting the target is defined as p/q. The probability of player 2 hitting the target is defined as r/s. We need to find the probability of player one winning the game.Let’s take an example to understand the problem, Inputp = 3, q = 5, r = 2, s = 5Output0.789Solution Approach*This approach requires ... Read More

In this problem we are given four values A, B, C, M(a prime number). Our task is to Find power of power under mod of a prime.We simply need to find the value of (A ^ (B ^ C)) (mod M).Let’s take an example to understand the problem, InputA = 3, B = 6, C = 2, M = 11Output3Explanation(A ^ (B ^ C)) = (3 ^ (6 ^ 2)) = (3 ^ (36))(mod 11) = 3Solution ApproachA simple solution to the problem is by directly calculating the values of the (A ^ (B ^ C)) , which is done ... Read More

In this problem we are given an array preOrder[] that represents the preorder traversal of the binary search tree. Our task is to Find postorder traversal of BST from preorder traversal.Let’s take an example to understand the problem, InputpreOrder[] = {5, 2, 4, 7, 12}Output{4, 2, 12, 7, 5}Solution ApproachA simple solution to the problem is to create a BST from the given preorder traversal. And then do postorder traversal of the tree. This solution is Ok but a more effective solution is, We will traverse the preorder array with a limit on values to separate values of left and ... Read More

In this problem we are given a number N which has only one set bit in its binary representation. Our task is to find the position of the only set bit. If the number has only one set bit return the position of the number otherwise print invalid number.Let’s take an example to understand the problem, InputN = 32Output6ExplanationBinary representation of the number is 10000.Solution ApproachOne fact to know before we proceed further is the number will have only 1 set bit if it is a power of 2. Otherwise it will have more number of set bits.A simple solution ... Read More

In this problem we are given a number N. Our task is to Find position of the given number among the numbers made of 4 and 7. The series consisting of 4 and 7 only is 4, 7, 44, 47, 74, 77, 444….Let’s take an example to understand the problem, InputN = 5Output74ExplanationSeries upto 5 terms is 4, 7, 44, 47, 74…Solution ApproachA simple solution to the problem is based on finding the pattern in the series.Here, every even position contains 7 in the end.And every odd position contains 4 in the end.So, we can find the series by going ... Read More