My professor is currently teaching the topic of Dynamic Memory Allocation along with pointers. I don't quite understand the following example:
#include <iostream>
#include <cstring>
#include <cstdlib>
using namespace std;
int main(void)
{
int i;
char * names[7]; // declare array of pointers to char
char temp[16];
// read in 7 names and dynamically allocate storage for each
for (i = 0; i < 7; i++)
{
cout << "Enter a name => ";
cin >> temp;
names[i] = new char[strlen(temp) + 1];
// copy the name to the newly allocated address
strcpy(names[i],temp);
}
// print out the names
for (i = 0; i < 7; i ++) cout << names[i] << endl;
// return the allocated memory for each name
for (i = 0; i < 7; i++) delete [] names[i];
return 0;
}
For the line that prints out the names, I don't understand how "names[i]" prints out the names. Shouldn't "names[i]" print out the pointers instead? Any help on this is greatly appreciated.
There is an overload of operator<<
with the following signature.
std::ostream& operator<<(std::ostream&, char const*);
which prints the null terminated string.
When you use
cout << names[i] << endl;
that overload is used.
You can see all the non-member overloads at http://en.cppreference.com/w/cpp/io/basic_ostream/operator_ltlt2 .
There is a member function overload of std::ostream
with the signature:
std::ostream& operator<<( const void* value );
However, in the overload resolution logic, the non-member function with char const*
as argument type is given higher priority.
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