Write a C$++$ program to print numbers in a triangle format.

Input an integer $H$ which represents the height of the triangle.

By using nested for loops, output numbers to form the triangle in the console.

Sample inputs $/$ outputs:

Enter height of the triangle : $1$

$1$

Enter height of the triangle : $2$

$1$

$12$

Enter height of the triangle : $3$

$12123$

Enter height of the triangle : $4$

$1121231234$

Enter height of the triangle : $5$

$1$

$12$

$\{\begin{array}{c}\text{:}123\end{array}$

$\{\begin{array}{c}\text{:}1234\end{array}$

$12345$