Important Problems on Arrays
By admin on August 13, 2016
Category:
Problem:

Find all pairs of integers within an array that sum to a specified value:
 Approach 1: Using hash table (more time efficient)
 Approach 2: Through sorting (more space efficient)
 Given an M x N matrix, if an element is 0, its entire row and column in the matrix should be set to 0.

You are given a 2Dimensional array (matrix) and a scale factor. You need to write a method to scale the 2D array according to the scale factor.

The signature of the method should be
 public static int[][] scale1(int[][] arr, int scale)

Example: if you are given a 2*3 array and scale factor is 3, the output array will be 6*9; the input and output arrays will be as follows:

Input
 1 2 3
 4 5 6

Output
 1 1 1 2 2 2 3 3 3
 1 1 1 2 2 2 3 3 3
 1 1 1 2 2 2 3 3 3
 4 4 4 5 5 5 6 6 6
 4 4 4 5 5 5 6 6 6
 4 4 4 5 5 5 6 6 6

Input

The signature of the method should be
Solution:
Refer to individual problems under corresponding problem category for solutions.