The famous Microsoft company once asked such an interview question when recruiting employees.

This is simple.

The actual problem is that three ants do not meet when their directions are equal, and they meet when their directions are unequal.

Since the direction of each ant is randomly selected, that is, the probability of each ant direction is 1/2

So you only need to consider whether the direction of the two ants is the same as that of the third ant. Just be consistent.

The probability that two ants are in the same direction as the third ant at the same time is 1/4

So the probability of not meeting each other is 1/4