[OS] User Processes and No. of their Childs

#!/bin/bash
#check if the number of arguments is right
if [ $# -ne 1 ]
then
    echo "USAGE: `basename $0` korisnik"
    exit 1
fi
#check if the out.txt file already exists
if [ -f out.txt ]
then
    rm out.txt
fi
#create the out.txt file
touch out.txt
echo "PID|Number of kids" >> out.txt
#get all process IDz of all the processes the argument user has started
pids=`ps -es | grep ^$1 | awk 'print $2;'`
#go thru all of em
for pid in $pids
do
    count=0
    #get the parent process IDz of the processes the user had started
    ppids=`ps -es | grep ^$1 | awk 'print $3;'`
    #if the process the user started is a parent of some other process then count++
    if [ $pid -eq $ppid ]
    then
        count=`expr $count + 1`
    fi
    #put in a line of text in out.txt for every cycle iteration
    #that consists of the PID of each process the user had started
    #and tha number of his child processes separted with tha | symbol
    echo "${pid}|${count}" >> out.txt
done
#print on screen tha output in need
cat out.txt