RosettaCodeData/Task/Babbage-problem/360-Assembly/babbage-problem.360

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* Find the lowest positive integer whose square ends in 269696
* The logic of the assembler program is simple :
* loop for i=524 step 2
* if (i*i modulo 1000000)=269696 then leave loop
* next i
* output 'Solution is: i=' i ' (i*i=' i*i ')'
BABBAGE CSECT beginning of the control section
USING BABBAGE,13 define the base register
B 72(15) skip savearea (72=18*4)
DC 17F'0' savearea (18 full words (17+1))
STM 14,12,12(13) prolog: save the caller registers
ST 13,4(15) prolog: link backwards
ST 15,8(13) prolog: link forwards
LR 13,15 prolog: establish addressability
LA 6,524 let register6 be i and load 524
LOOP LR 5,6 load register5 with i
MR 4,6 multiply register5 with i
LR 7,5 load register7 with the result i*i
D 4,=F'1000000' divide register5 with 1000000
C 4,=F'269696' compare the reminder with 269696
BE ENDLOOP if equal branch to ENDLOOP
LA 6,2(6) load register6 (i) with value i+2
B LOOP branch to LOOP
ENDLOOP XDECO 6,BUFFER+15 edit registrer6 (i)
XDECO 7,BUFFER+34 edit registrer7 (i squared)
XPRNT BUFFER,L'BUFFER print buffer
L 13,4(0,13) epilog: restore the caller savearea
LM 14,12,12(13) epilog: restore the caller registers
XR 15,15 epilog: set return code to 0
BR 14 epilog: branch to caller
BUFFER DC CL80'Solution is: i=............ (i*i=............)'
END BABBAGE end of the control section