Shell Programming and Scripting

Hello guys I am new to awk programming. I need the below required script which can perform the following.
I have a file containing below data.

SNA NoCRD = 131
SNA OBarr = 3
SNC NoCRD = 76
SNC OBarr = 1
SND NoCRD = 155
SND OBarr = 5
SNE NoCRD = 100
SNE OBarr = 1
SNF NoCRD = 131
SNF OBarr = 5
SNG NoCRD = 123
SNG OBarr = 2
SNH NoCRD = 129
SNI NoCRD = 121
SNI OBarr = 3
SNJ NoCRD = 124
SNJ OBarr = 4
SNK NoCRD = 118
SNK OBarr = 3
SNM UnK = 5
SNM NoCRD = 391
SNM OBarr = 3
SNN NoCRD = 101
SNN OBarr = 7.
I want to replace the codes with a number but with a format like,

If it is SNA then just print only a digit like 1. since in my case I have SNA for 2 times with two more values, so I want to print only a one line above those 2 values but not with SNA infront of each line. similarly i want to do for the rest of the file. and then dump it in a new file.

Kindly help me in this regards. I will be very grateful.

Thanks in Advance

I've down this with arrays. (hint!) Populate the array in the main body of your awk script and use the END part of your script to output the contents of the array. (hint:hint!)

HTH

Dear I am very new to awk. Kindly help me with code example. or provide a code for the mentioned case.

Thanks