[C]: printf / scanf functions are evil

I'm just starting to learn C and the first exercise made in class was to make a program that prints the sum of two integers.

This program:

#include <stdio.h>
#include <stdlib.h>
int main (void) {
  int n1,n2;
  printf("1st int: ");
  scanf("%d",&n1);
  printf("2nd int: ");
  scanf("%d",&n2);
  printf("Sum = %d\n",n1+n2);
  return EXIT_SUCCESS;
}

I showed it to some of my older classmates and went batshit insane with it saying: DO NOT USE PRINTF AND SCANF, THEY ARE NOT FUCKING SAME and other stuff.

Will someone please input on this matter?
Thank you!

printf is fine, tell your friends to stop being idiots.
scanf isn't unsafe (as long as you wrap it in some error recovery code), but it's basically worthless for actual input.  Use readline or fgets, then sscanf the result or parse it yourself.