The `auto` keyword enables a variable's declaration without specification of its data type.

#include <iostream>
using namespace std;

int main() {

  auto unknown_variable = "eleven";

  cout<< unknown_variable;

}

The `auto` keyword is particularly useful with function calls, especially in cases where​ the function return type is not certain.

#include <iostream>
using namespace std;

double num_generator(){
    return 401.8;
}

int main() {

  auto unknown_variable = num_generator();

  cout<< unknown_variable;

}



What is the auto keyword in C++?

The auto keyword allows declaring variables without specifying the type, useful for uncertain function return types.