answer.code: In function ‘int main()’:
answer.code:3:3: error: ‘printf’ was not declared in this scope
    3 |   printf("%d %d\n",n,m);
      |   ^~~~~~
answer.code:1:1: note: ‘printf’ is defined in header ‘<cstdio>’; did you forget to ‘#include <cstdio>’?
  +++ |+#include <cstdio>
    1 | int main() {
answer.code:24:25: error: ‘puts’ was not declared in this scope
   24 |   for (int i=0;i<n;++i) puts(mp[i]);
      |                         ^~~~