A really nice LeetCode solution

Here's a solution to this LeetCode problem:

// hack to fix integer overflow problems
static uint32_t mySqrt_exact(uint32_t x) {
    uint32_t r = 0;
    for (uint32_t b = 1 << 15; b > 0; b >>= 1) {
        uint32_t nr = r | b;
        if (nr * nr <= x) {
            r = nr;
        }
    }
    return r;
}

int mySqrt(int x) {
    return (int) mySqrt_exact((uint32_t) x);
}

This is basically a bit-level binary search. I thought that this was cool enough to warrant a blog post.