Check out example codes for "error: ‘cout’ was not declared in this scope". It will help you in understanding the concepts better.
Code Example 1
#include <iostream>
using namespace std;
adding above two lines before main will help you
NOTE:
note: suggested alternative:
In file included from class.cpp:1:0:
/usr/include/c++/7/iostream:61:18: note: ‘std::cout’
extern ostream cout; /// Linked to standard output
^~~~
Code Example 2
#include<iostream>
using namespace std; //use this
int main(){
char t = 'f';
char *t1;
char **t2;
cout<<t;
return 0;
}
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