Programs for printing different patterns in Bash

Given the number N which represents the number of rows and columns, print the different following patterns in Bash. 

• Pattern-1:

Input: 6
Output:
     #
    ##
   ###
  ####
 #####
######

• Use nested loop to print the given pattern. The first loop represents the row and the second loop represents the column. 

BASH

# Program to print the
# given pattern

# Static input for N
N=5

# variable used for
# while loop
i=0
j=0

while [ $i -le `expr $N - 1` ]
do
    j=0

    while [ $j -le `expr $N - 1` ]
    do
        if [ `expr $N - 1` -le `expr $i + $j` ]
        then
          # Print the pattern
          echo -ne "#"
        else
          # Print the spaces required
          echo -ne " "
        fi
        j=`expr $j + 1`
    done
    # For next line
    echo

    i=`expr $i + 1`
done

Output:

    #
   ##
  ###
 ####
#####

• Pattern-2:

Input: 3
Output:
    #
   ###
  #####

• Use nested loops to print the left part and right part of the pattern. The details are explained in the code: 

BASH

# Program in Bash to
# print pyramid

# Static input to the
# number
p=7;

for((m=1; m<=p; m++))
do
    # This loop print spaces
    # required
    for((a=m; a<=p; a++))
    do
      echo -ne " ";
    done

    # This loop print the left
    # side of the pyramid
    for((n=1; n<=m; n++))
    do
      echo -ne "#";
    done

    # This loop print right
    # side of the pyramid.
    for((i=1; i<m; i++))
    do
      echo -ne "#";
    done

    # New line
    echo;
done

Output:

        #
       ###
      #####
     #######
    #########
   ###########
  #############