lc3 assembly, How to add two user input numbers and output it? -

after storing 2 numbers, how add them , display answer??

this have far, need output answer @ end. appreciated:

.orig x3000  lea r0, ln1 puts  lea r2, no1  loop1  getc  str r0, r2, 0        add r2, r2, 1        add r1, r0, -10      brz out1  out           brnzp loop1   out1  lea r0, ln2  puts  lea r2, no2  loop2  getc  str r0, r2, 0        add r2, r2, 1        add r1, r0, -10      brz out2  out           brnzp loop2   out2  lea r0, ln3 puts   halt  no1 .blkw 15  no2 .blkw 15  ln3 .stringz "\nsum: "  ln1 .stringz "\nenter first number: "  ln2 .stringz "\nenter second number: "  .end