assembly - use slt to check unsigned integer addition carry flag mips

Question

I'm new to Assembly and I know this is a fair easy question. I supposed to do unsigned integer addition for $a0 and $a2 and store the result in $v0 by checking the carry flag.

The assignment says:

Use only addu, not add, for adding and use slt for determining if the addition of two unsigned integers produced a carry, without using conditional branch instructions.

Here is my code:

addu $v0, $a0, $a2
sltu $t0, $v0, $a0

For this code, if a carry is produced, $t0 equals 1. But the question said use only slt to check the carry flag and no conditional branch instruction can be used. I'm a little bit confused about how this is gonna to work. Any help would be appreciated.

Answer 1

好的，教授说他答错了，使用addu和没问题sltu。