Traverse a given Matrix using Recursion (original) (raw)

Easy problems on Matrix

• Print matrix in zig-zag fashion Given a matrix of 2D array of n rows and m columns. Print this matrix in ZIG-ZAG fashion as shown in figure. Example: Input: {{1, 2, 3}{4, 5, 6}{7, 8, 9}}Output: 1 2 4 7 5 3 6 8 9Input : [[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16]]Output:: 1 2 5 9 6 3 4 7 10 13 14 11 8 12 15 16Thi 10 min read

• Program for scalar multiplication of a matrix Given a 2D matrix mat[][] with n rows and m columns and a scalar element k, the task is to find out the scalar product of the given matrix.Examples: Input: mat[][] = [[2, 3], [5, 4]]k = 5Output: [[10, 15], [25, 20]]Input:mat[][] = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]k = 4Output: [[4, 8, 12], [16, 20, 2 4 min read

• Print a given matrix in spiral form Given a matrix mat[][] of size m x n, the task is to print all elements of the matrix in spiral form.Examples: Input: mat[][] = [[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16]]Output: [ 1, 2, 3, 4, 8, 12, 16, 15, 14, 13, 9, 5, 6, 7, 11, 10 ]Example of matrix in spiral formInput: mat[] 14 min read

• Find distinct elements common to all rows of a matrix Given a n x n matrix. The problem is to find all the distinct elements common to all rows of the matrix. The elements can be printed in any order. Examples: Input : mat[][] = { {2, 1, 4, 3}, {1, 2, 3, 2}, {3, 6, 2, 3}, {5, 2, 5, 3} } Output : 2 3 Input : mat[][] = { {12, 1, 14, 3, 16}, {14, 2, 1, 3, 15+ min read

• Find unique elements in a matrix Given a matrix mat[][] having n rows and m columns. The task is to find unique elements in the matrix i.e., those elements which are not repeated in the matrix or those elements whose frequency is 1. Examples: Input: mat[][] = [[2, 1, 4, 3], [1, 2, 3, 2], [3, 6, 2, 3], [5, 2, 5, 3]]Output: 4 6Input: 5 min read

• Find maximum element of each row in a matrix Given a matrix mat[][], the task is to find the maximum element of each row.Examples: Input: mat[][] = [[1, 2, 3] [1, 4, 9] [76, 34, 21]]Output :3976Input: mat[][] = [[1, 2, 3, 21] [12, 1, 65, 9] [1, 56, 34, 2]]Output :216556The idea is to run the loop for no_of_rows. Check each element inside the r 4 min read

• Shift matrix elements row-wise by k Given a square matrix mat[][] and a number k. The task is to shift the first k elements of each row to the right of the matrix. Examples : Input : mat[N][N] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}} k = 2 Output :mat[N][N] = {{3, 1, 2} {6, 4, 5} {9, 7, 8}} Input : mat[N][N] = {{1, 2, 3, 4} {5, 6, 7, 8} {9 6 min read

• Swap major and minor diagonals of a square matrix Given a square matrix mat[][] of order n*n, the task is to swap the elements of major and minor diagonals.The major and minor diagonal matrix explanation is given below:Major Diagonal Elements of a Matrix: The Major Diagonal Elements are the ones that occur from the Top Left of the Matrix Down To th 6 min read

• Squares of Matrix Diagonal Elements Given an integer matrix mat[][] of odd dimensions, the task is to find the square of the elements of the Primary and Secondary diagonals.The Primary and Secondary diagonal matrix explanation is given below:Primary Diagonal Elements of a Matrix: The Primary Diagonal Elements are the ones that occur f 11 min read

• Sum of middle row and column in Matrix Given an integer matrix of odd dimensions (3 * 3, 5 * 5). then the task is to find the sum of the middle row & column elements. Examples: Input : 2 5 7 3 7 2 5 6 9 Output : Sum of middle row = 12 Sum of middle column = 18 Input : 1 3 5 6 7 3 5 3 2 1 1 2 3 4 5 7 9 2 1 6 9 1 5 3 2 Output : Sum of 7 min read

• Program to check idempotent matrix Given a square matrix mat[][] of order n*n, the task is to check if it is an Idempotent Matrix or not.Idempotent matrix: A matrix is said to be an idempotent matrix if the matrix multiplied by itself returns the same matrix, i.e. the matrix mat[][] is said to be an idempotent matrix if and only if M 5 min read

• Program to check diagonal matrix and scalar matrix Given a square matrix mat[][] of order n*n, the task is to check if it is a Diagonal Matrix and Scalar matrix.Diagonal Matrix: A square matrix is said to be a diagonal matrix if the elements of the matrix except the main diagonal are zero. A square null matrix is also a diagonal matrix whose main di 9 min read

• Program to check Identity Matrix Given a square matrix mat[][] of order n*n, the task is to check if it is an Identity Matrix.Identity Matrix: A square matrix is said to be an identity matrix if the elements of main diagonal are one and all other elements are zero. The identity Matrix is also known as the Unit Matrix. Examples: Inp 5 min read

• Mirror of matrix across diagonal Given a 2-D array of order N x N, print a matrix that is the mirror of the given tree across the diagonal. We need to print the result in a way: swap the values of the triangle above the diagonal with the values of the triangle below it like a mirror image swap. Print the 2-D array obtained in a mat 14 min read

• Program for addition of two matrices Given two N x M matrices. Find a N x M matrix as the sum of given matrices each value at the sum of values of corresponding elements of the given two matrices. Approach: Below is the idea to solve the problem.Iterate over every cell of matrix (i, j), add the corresponding values of the two matrices 5 min read

• Program for subtraction of matrices Given two m x n matrices m1 and m2, the task is to subtract m2 from m1 and return res.Input: m1 = {{1, 2}, {3, 4}}, m2 = {{4, 3}, {2, 1}}Output: {{-3, -1}, {1, 3}}Input: m1 = {{3, 3, 3}, {3, 3, 3}}, m1 = {{2, 2, 2}, {1, 1, 1}},Output: {{1, 1, 1}, {2, 2, 2}},We traverse both matrices element by eleme 5 min read