Empty rows filling using other reference coloum

[Anbumani]

Hi,

i have two scenario, my main object to fill the  External city blank from Internal city by using reference.

1st Scenario

i have only one internal row, with using ref column i want to bring the city to external row

leg	Value	City	ref
External	2		253
External	3		253
External	1		253
Internal	6	Chennai	253

2nd scenario

i have two internal line by using ref column and value, i need to bring the city to external, like for Chennai we have value 4 for external any number which sum to 4 i need to give Chennai and remaining I need to give Delhi

leg	Value	City	ref
External	2		253
External	3		253
External	1		253
External	1		253
Internal	4	Chennai	253
Internal	3	Delhi	253

kindly help how to achieve this using Alteryx 

[binu_acs]

@Anbumani with the help of multi-row formula you can achieve the result of scnario1, Sample attached

what is the expected result for the second scnario?

[Anbumani]

@binu_acs for second scenario if you see the table for external leg the total value we have 7 and for internal we have two separate value one is 3 for Delhi and 4 for Chennai, by using ref column and I want to bring the city to external leg but it should sum the external value for any sum of value 4 it should give Chennai and for others its should give Delhi.

for 1st scenario I want to use the ref column and fill the city and along with this it should satisfiy the second scenario 

[binu_acs]

@Anbumani Can you provide the expected result for scnario2 for better understanding?

[Anbumani]

@binu_acs Like the red highlighted i need the output 

leg	Value	City	ref
External	2	Chennai	253
External	3	Delhi	253
External	1	Chennai	253
External	1	Chennai	253
Internal	4	Chennai	253
Internal	3	Delhi	253

[binu_acs]

@Anbumani but if you take 3+1 it would give you 4 as well , that means External 3 also fall in Chennai I guess?