Output of C++ code

Question

Can someone explain how this code works? Also, why does it issue a warning in the C compiler but not the C++ compiler?

#include <iostream>
using namespace std;

int main() {
int a[][3]={1,2,3,4,5,6};
int (*ptr)[3] = a;
printf("%d %d ", (*ptr)[1], (*ptr)[2]);
++ptr;
printf("%d %d",(*ptr)[1], (*ptr)[2]);
return 0;
}

https://code.sololearn.com/cIp2L0q5kGua/#cpp

Answer 1

Here u uses iostream header file which belongs to c++