How to make a program that finds id's of xinput devices and sets xinput some settings

You can do something like the following.

if [ "$SEARCH" = "" ]; then 
    exit 1
fi

ids=$(xinput --list | awk -v search="$SEARCH" \
    '$0 ~ search {match($0, /id=[0-9]+/);\
                  if (RSTART) \
                    print substr($0, RSTART+3, RLENGTH-3)\
                 }'\
     )

for i in $ids
do
    xinput set-prop $i 'Device Accel Profile' -1
    xinput set-prop $i 'Device Accel Constant Deceleration' 2.5
    xinput set-prop $i 'Device Accel Velocity Scaling' 1.0
done

So with this you first find all the IDs which match the search pattern $SEARCH and store them in $ids. Then you loop over the IDs and execute the three xinput commands.

You should make sure that $SEARCH does not match to much, since this could result in undesired behavior.

If the device name is always the same, in this case Logitech G700 Laser Mouse, you can search for matching device IDs by running

xinput list --id-only 'Logitech G700 Laser Mouse'

My 2 cents for a Logitech Gaming Mouse G502

#!/bin/sh


for id in `xinput --list|grep 'Logitech Gaming Mouse G502'|perl -ne 'while (m/id=(\d+)/g){print "$1\n";}'`; do
    # echo "setting device ID $id"
    notify-send -t 50000  'Mouse fixed'
    xinput set-prop $id "Device Accel Velocity Scaling" 1
    xinput set-prop $id "Device Accel Constant Deceleration" 3
done