foo.cc: In function 'int main()':
foo.cc:12:14: warning: format '%ld' expects argument of type 'long int*', but argument 2 has type 'long long int*' [-Wformat=]
   12 |     scanf("%ld", &a[i]);
      |            ~~^   ~~~~~
      |              |   |
      |              |   long long int*
      |              long int*
      |            %lld
foo.cc:31:13: warning: format '%ld' expects argument of type 'long int', but argument 2 has type 'long long int' [-Wformat=]
   31 |   printf("%ld", num);
      |           ~~^   ~~~
      |             |   |
      |             |   long long int
      |             long int
      |           %lld
foo.cc:8:18: warning: unused variable 'm' [-Wunused-variable]
    8 |  int i, j, k, n, m;
      |                  ^
foo.cc:9:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |   scanf("%d%d", &n, &k);
      |   ~~~~~^~~~~~~~~~~~~~~~
foo.cc:12:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |     scanf("%ld", &a[i]);
      |     ~~~~~^~~~~~~~~~~~~~

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