sll $t0, $s0, 2       # $t0 = f * 4
add $t0, $s6, $t0  # $t0 = &A[f]
sll $t1, $s1, 2       # $t1 = g * 4
add $t1, $s7, $t1  # $t1 = &B[g]
lw $s0, 0($t0)      # f = A[f]
addi $t2, $t0, 4
lw $t0, 0($t2)
add $t0, $t0, $s0
sw $t0, 0($t1)