foo.cc: In function 'int main()':
foo.cc:15:14: warning: format '%lld' expects argument of type 'long long int*', but argument 2 has type 'int*' [-Wformat=]
   15 |    scanf("%lld",&cost[i][j]);
      |           ~~~^  ~~~~~~~~~~~
      |              |  |
      |              |  int*
      |              long long int*
      |           %d
foo.cc:11:22: warning: unused variable 'k' [-Wunused-variable]
   11 |  long long int n,i,j,k;
      |                      ^
foo.cc:12:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |  scanf("%lld",&n);
      |  ~~~~~^~~~~~~~~~~
foo.cc:15:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 |    scanf("%lld",&cost[i][j]);
      |    ~~~~~^~~~~~~~~~~~~~~~~~~~

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