// Write a function that rotates a list by k elements. For example, [1, 2, 3, 4, 5, 6] rotated by two becomes // [3, 4, 5, 6, 1, 2].
// Try solving this without creating a copy of the list. How many swap or move operations do you need?
#include <iostream>
#include <string>
#include <vector>
using namespace std;
vector<int> rotateVector(vector<int> vec, int k)
{
if (vec.size() < 2)
return vec;
int next;
int prev;
for (unsigned i = 0; i < k; ++i)
{
prev = vec[vec.size() - 1];
for (unsigned j = 0; j < vec.size(); ++j)
{
int curr = vec[j];
vec[j] = prev;
prev = curr;
}
}
return vec;
}
int main()
{
int k = 2;
vector<int> vec;
vec.push_back(1);
vec.push_back(2);
vec.push_back(3);
vec.push_back(4);
vec.push_back(5);
vec.push_back(6);
auto result = rotateVector(vec, k);
for (unsigned i = 0; i < result.size(); ++i)
{
cout << result[i] << ", ";
}
return 0;
}
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