CODEWITHSUNDEEP
javaarraysmatrixmethods
Rods2292
Rods2292

Reputation: 675

Printing line of a given matrix

I'm trying to made a method that receives a matrix and prints its lines. For example:

line nb 1 : 3 2 5 6 
line nb 2 : 7 9 0 1 4 3 
line nb 3 : 3 5 3

I'd like to know why I cannot print the lines of the given matrix using this code. And also, why I cannot increment the variable k, that shows me the number of the line.

When I run this code it does not increment k. It always shows me the number 1 for the line

How can I fix my code?

public static void PrintLine(int[][] matrix){

for (i = 0; i < matrix.length; ++i){   // Loop all long the lines of the matrix
            int k = 1;     // Number of the line
            System.out.print("Line nb " + k + matrix[i]);
            k = k+1;   // Increment the number of the line by 1
        }

}

Upvotes: 0

Views: 55

Answers (3)

Sean F
Sean F

Reputation: 2390

As other have pointed out the scope of your k is incorrect, you can just use the value of i, also when you print your array you are getting the object reference details, you can use Arrays.toString() to print the values from an Array.

for (int i = 0; i < matrix.length; ++i) {
  System.out.print("Line nb " + i +": "+ Arrays.toString(matrix[i]));
}

Upvotes: 0

vvg
vvg

Reputation: 6385

Your k variable is initialized inside for loop. It means on each iteration it will be new variable. With initial 1 value. Move it's itialization out of the loop:

            int k = 1;     // Number of the line
for (i = 0; i < matrix.length; ++i){   // Loop all long the lines of the matrix

Upvotes: 0

Jae Heon Lee
Jae Heon Lee

Reputation: 1101

It's not so much that k does not get incremented; rather, you increment k only to discard it immediately, because the scope of the variable k is restricted to a single iteration (i.e., within the curly braces). The following should work:

for (int i = 0, k = 0; i < matrix.length; ++i, ++k) {
  /* work in terms of i and k */
}

which, in your case, simplifies to using i and k for the same purpose:

for (int i = 0; i < matrix.length; ++i) {
  System.out.print("Line nb " + i + matrix[i]");
}

Upvotes: 1

Related Questions