# Ruby program to print the left diagonal matrix

Ruby Example: Write a program to print the left diagonal matrix.
Submitted by Nidhi, on January 25, 2022

Problem Solution:

In this program, we will create a matrix using the 2D array. Then we read elements of the matrix from the user. After that, we will print the left diagonal matrix.

Program/Source Code:

The source code to print the left diagonal matrix is given below. The given program is compiled and executed successfully.

```# Ruby program to print the
# left diagonal matrix

TwoDArr = Array.new(3){Array.new(3)}

printf "Enter elements of MATRIX:\n";
i = 0;
while (i < 3)
j = 0;
while (j < 3)
printf "ELEMENT [%d][%d]: ", i, j;
TwoDArr[i][j] =  gets.chomp.to_i;
j = j + 1;
end
i = i + 1;
end

printf "MATRIX:\n";
i = 0;
while (i < 3)
j = 0;
while (j < 3)
print TwoDArr[i][j]," ";
j = j + 1;
end
i = i + 1;
print "\n";
end

printf("Left diagonal of matrix:\n")
i = 0;
while (i < 3)
j = 0;
while (j < 3)
if (i == j)
printf "%d ", TwoDArr[i][j];
else
printf(" ");
end
j = j + 1;
end
i = i + 1;
print "\n";
end
```

Output:

```Enter elements of MATRIX:
ELEMENT [0][0]: 1
ELEMENT [0][1]: 2
ELEMENT [0][2]: 3
ELEMENT [1][0]: 4
ELEMENT [1][1]: 5
ELEMENT [1][2]: 6
ELEMENT [2][0]: 7
ELEMENT [2][1]: 8
ELEMENT [2][2]: 9
MATRIX:
1 2 3
4 5 6
7 8 9
Left diagonal of matrix:
1
5
9
```

Explanation:

In the above program, we created a 3X3 matrix TwoDArr using the 2D array. Then we read the elements of the matrix. After that, we printed the left diagonal of the matrix.

Preparation

What's New

Top Interview Coding Problems/Challenges!