I am trying to create a sorting function with the parameters being a pointer of a list and I am trying to access an element of the given list. Hopefully this code speaks for the problem better than I can:
void bubbleSort(std::vector<int> *L) { unsigned int i = 0; int temp; while(isSorted(*L)) { if(i==L->size()-1) { i = 0; } if(i<L[i]/*<-ERROR here.*/) { temp = L[i+1]; // ERROR HERE L[i+1] = L[i]; // ERROR HERE L[i] = temp; // ERROR HERE } } } You don't need to painfully dereference every individual use of L (and indeed doing so is error-prone, as you've demonstrated by missing one in your answer).
Instead, just write:
void bubbleSort(std::vector<int> *Lptr) { auto &L = *Lptr; and keep the rest of the code the same.
NB. It would be even better to change the function itself, to
void bubbleSort(std::vector<int> &L) { as it should have been written in the first place, but I'm assuming there's some artificial reason you can't do that.
void bubbleSort(std::span<int> L) {.
template <typename T> void bubbleSort(std::span<T> L). Potentially const T.The function accepts a pointer to an object of type std::vector<int>.
void bubbleSort(std::vector<int> *L) { To access the original vector using the pointer, you can write either *L or L[0]. That is, both expressions yield an lvalue reference of type std::vector<int> & to the vector.
To get the i-th element of the vector using the subscript operator through the pointer, you can write either (*L)[i] or L[0][i],
However, in this if statement:
if(i<L[i]/*<-ERROR here.*/) { You are trying to compare the variable i of type unsigned int to the object L[i] of type std::vector<int>. When i is not equal to 0, this yields a non-existent object of the vector type.
It seems you mean something like the following instead:
if ( (*L)[i] < (*L)[i+1] ) { or:
if ( L[0][i] < L[0][i+1] ) { or, vice versa:
if ( L[0][i+1] < L[0][i] ) { Depending on whether the vector is sorted in ascending or descending order.
Pay attention to the fact that there is no sense in declaring the parameter as a pointer to a std::vector<int>. The function would be much clearer and readable if it accepted the vector by reference instead:
void bubbleSort(std::vector<int> &L) { In this case, the if statement would look like this:
if ( L[i] < L[i+1] ) { 
Although I prefer to change the source code as other answer. But, for this question, you can use ->at() function to access the element in a vector pointer.
if(i<L->at(i)) { temp = L->at(i+1); L->at(i+1) = L->at(i); L->at(i) = temp; } 
Lis a pointer to a vectorL[i]isith vector it's pointing to, instead of theith value in the first vector the pointer is pointing to, as is your clear intention here.Lis a pointer to a vector you need(*L)[i]everywhere you try to indexL. You should probable passLas a referencevoid bubbleSort(std::vector<int> &L)to avoid this.std::swap().