What's the error with this code?

Question

#include<iostream>
#include<string>
using namespace std;
int main()
{
string mystring='This is a string';
cout<<mystring;
return 0;
}

Answer 1

You are using ' to define a string instead of "
So it is:
string mystring ="This is a string"

' is used to define a char (single character).

Answer 2

Thank you Théophile and Gellert .