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Kotlin program to print upper triangular matrix

Here, we are going to implement a Kotlin program to print the upper triangular of a given matrix. Submitted by IncludeHelp, on May 08, 2020

Kotlin - Print upper triangular matrix

An upper triangular matrix is a matrix in which all the lower triangular elements are zero, or all the elements below the principle diagonal will be zero.

Given a matrix, we have to print its upper triangular.

Example

Input:
matrix:
[2, 3, 4]
[5, 6, 7]
[8, 9, 8]

Output:
Upper Triangular of Matrix :
[2, 3, 4]
[0, 6, 7]
[0, 0, 8]

Program to print upper triangular matrix in Kotlin

package com.includehelp

import java.util.*

// Main function, Entry Point of Program
fun main(args: Array<String>) {

    //variable of rows and col
    val rows: Int
    val column: Int

    //Input Stream
    val scanner = Scanner(System.`in`)

    //Input no of rows and column
    print("Enter the number of rows and columns of matrix : ")
    rows   = scanner.nextInt()
    column = scanner.nextInt()

    if(rows!=column) {
        println("Matrix should be Square matrix , Rows and Col size must be Same !!")
        return
    }

    //Create Array
    val matrixA     = Array(rows) { IntArray(column) }

    //Input Matrix
    println("Enter the Elements of First Matrix ($rows X $column} ): ")
    for(i in matrixA.indices){
        for(j in matrixA[i].indices){
            print("matrixA[$i][$j]: ")
            matrixA[i][j]=scanner.nextInt()
        }
    }

    //print Matrix A
    println("Matrix A : ")
    for(i in matrixA.indices){
        println("${matrixA[i].contentToString()} ")
    }

    //get Upper Triangular of matrix
    for(i in matrixA.indices){
        for(j in matrixA[i].indices){
            if(j<i) matrixA[i][j]=0
        }
    }

    //print Matrix A
    println("Upper Triangular of Matrix : ")
    for(i in matrixA.indices){
        println("${matrixA[i].contentToString()} ")
    }
}

Output

Run 1:
Enter the number of rows and columns of matrix : 4
3
Matrix should be Square matrix , Rows and Col size must be Same
---
Run 2:
Enter the number of rows and columns of matrix : 3
3
Enter the Elements of First Matrix (3 X 3} ):
matrixA[0][0]: 2
matrixA[0][1]: 3
matrixA[0][2]: 4
matrixA[1][0]: 5
matrixA[1][1]: 6
matrixA[1][2]: 7
matrixA[2][0]: 8
matrixA[2][1]: 9
matrixA[2][2]: 8
Matrix A :
[2, 3, 4]
[5, 6, 7]
[8, 9, 8]
Upper Triangular of Matrix :
[2, 3, 4]
[0, 6, 7]
[0, 0, 8]