Example of Big O of 2^n

Question

So I can picture what an algorithm is that has a complexity of n^c, just the number of nested for loops.

for (var i = 0; i < dataset.len; i++ {
    for (var         


        

Answer 1

c^N = All combinations of n elements from a c sized alphabet.

More specifically 2^N is all numbers representable with N bits.

The common cases are implemented recursively, something like:

vector<int> bits;
int N
void find_solution(int pos) {
   if (pos == N) {
     check_solution();
     return;
   }
   bits[pos] = 0;
   find_solution(pos + 1);
   bits[pos] = 1;
   find_solution(pos + 1);
}