Java Matrix doesn't prints last row

Question

package com.test;
import java.util.Scanner;

public class Main {

    public static void main(String args[]) {
        System.out.println("Rows = ?");
        Scanner sc = new Scanner(System.in);
        if(sc.hasNextInt()) {
            int nrows = sc.nextInt();
            System.out.println("Columns = ?");
            if(sc.hasNextInt()) {
                int ncolumns = sc.nextInt();
                char matrix[][] = new char[nrows][ncolumns];
                System.out.println("Enter matrix");
                for (int row = 0; sc.hasNextLine() && nrows > row; row++) {
                        matrix[row] = sc.nextLine().toCharArray();
                }
                for (int row = 0; row < nrows; row++) {
                    for (int column = 0; column < matrix[row].length; column++) {
                        System.out.print(matrix[row][column] + "\t");
                    }
                    System.out.println();
                }
            }
        }
    }
}

So my programm reads matrix and prints it, but the last row doesn't prints. I think, that problem in for-loop, which prints columns.

Input:

2
2
-=
=-

Actual output:

-=

Expected output:

-=
=-

Answer 1

You need to change

for (int row = 0; sc.hasNextLine() && nrows > row; row++) {
        matrix[row] = sc.nextLine().toCharArray();
}

to

sc.nextLine();
for (int row = 0; nrows > row; row++) {
        matrix[row] = sc.nextLine().toCharArray();
}

Main problem is that nextInt(), or other nextXXX() methods except nextLine() do not consume line separators, which means that when you input 2 (and press enter) actual input will look like 2\n or 2\r\n or 2\r depending on OS.

So with nextInt you are reading only value 2 but Scanner's cursor will be set before line separators like

2|\r\n
 ^-----cursor

which will make nextLine() return empty String, because there ware no characters between cursor and next line separators.

So to actually read line after nextInt (not the empty string) you need to add another nextLine() to set cursor after these line separators.

2\r\n|
     ^-----cursor - nextLine() will return characters from here 
                    till next line separators or end of stream

---

BTW to avoid this problem you can use

int i = Integer.parseInt(sc.nextLine());

instead of int i = nextInt().