Help with Using "while" loop to output series of numbers

Shell Programming and Scripting
1

Trying to use "while" loop command to create a series of numbers that looks like the following:
0 .
1 0 .
2 1 0 .
3 2 1 0 .
4 3 2 1 0 .
5 4 3 2 1 0 .
6 5 4 3 2 1 0 .
7 6 5 4 3 2 1 0 .
8 7 6 5 4 3 2 1 0 .
9 8 7 6 5 4 3 2 1 0 .

I am very new to shell scripting and any help would be greatly appreciated.
Thanks

2

Have you tried any pseudocode yet? If not, please try and then we can suggest the unix command to be used for each of the steps.

3

post your code what you have tried. its simple. u can use two while loops.. try it u will get it.. if not then post the code, someone will fix it for sure..

4 
#!/bin/bash
i="0"
p="."
while [ $i -lt 10 ]
        do
        p="$i $p"
        echo $p
        ((i++))
done
1 Like
5

another way:

i=0
while [ $i -le 9 ]; do
        j=$i
        while [ $j -ge 0 ]; do
                echo -n "$j "
                (( j-- ));
        done
        echo "."
        ((i++))
done
1 Like
6

Just for test: awk

awk 'BEGIN {a="."; for (i=0;i<=9;i++) {a=i" "a;print a}}'
7

Without explicit looping:

seq 0 9 | sed '1s/$/ ./; 1!G; y/\n/ /; h'

Regards,
Alister

1 Like
8

lazy math-less way:

for N in 0 1 2 3 4 5 6 7 8 9
do
        STR="$STR $N"
        echo "$STR ."
done