avector index out of bound issue C++

[AbdulBasee]

vector shortBubbleSort(vector avector){ //the vector for bubble sort
bool exchanges = true;
int passnum = avector.size();
//while vector size is greater than 0 and exchanges = true
while (passnum > 0 && exchanges) {
exchanges = false;
//loops through vector, exchanging values until it reaches the end of vector.
for(int i = 0; i < passnum; i++){
if(avector[i] > avector[i+1]){
exchanges = true;
int temp = avector[i];
avector[i] = avector[i+1];
avector[i+1] = temp;
}
}
//subtracts from the passnum variable so that the next passthrough is one less
//than the previous, because the largest value has already 'bubbled' all the way up.
passnum = passnum - 1;
}
return avector;

The comparison of avector[i] with avector[i + 1] is going to create an issue when we are comparing the last element. The error will be as follows: "Invalid read of size 4" for avector of size four.