C++ References and Pointers

A reference is another name for a variable. Passing by reference lets a function change the caller's variable without copying it. Pointers hold addresses and work like in C.

ExampleC++

#include <iostream>
using namespace std;

void addOne(int &x) { x++; }
void addOnePtr(int *p) { (*p)++; }

int main() {
  int a = 10;
  addOne(a);
  cout << a << endl;      // 11

  addOnePtr(&a);
  cout << a << endl;      // 12

  int &alias = a;
  alias = 50;
  cout << a << endl;      // 50
  return 0;
}

Output

11
12
50

Quick check

What does passing by reference allow?

A function to change the original variableFaster compile timesReturning two values

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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