Write a function "swapElements$()"$ that swaps two adjacent elements of indices $\text{'}$i$\text{'}$ and $\text{'}$i$+1\text{'}$ of the same vector $"$vi$"$ that stores integer elements.

void swapElements$($vector & vi$,$ int i$)$;

However, for the last element at position i$=$vi$.$size$()-1,$ there is no $"$i$+1".$ So the operation should not be perform and nothing should happen, i$.$e$.,$ the vector remains the same.