answer.code:150:1: error: expected unqualified-id before numeric constant
  150 | 11
      | ^~
answer.code: In function ‘int main()’:
answer.code:35:12: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   35 |     freopen("a.in","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~
answer.code:36:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   36 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
answer.code:39:18: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   39 |             scanf("%lld",&A[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~~~
answer.code:42:18: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   42 |             scanf("%lld",&C[i][j]),C[i][j]=(C[i][j]+mod)%mod;
      |             ~~~~~^~~~~~~~~~~~~~~~~