foo.c: In function 'main':
foo.c:6:11: warning: format '%ld' expects argument of type 'long int *', but argument 2 has type 'long long int *' [-Wformat=]
  scanf("%ld%ld",&n,&m);
         ~~^     ~~
         %lld
foo.c:6:14: warning: format '%ld' expects argument of type 'long int *', but argument 3 has type 'long long int *' [-Wformat=]
  scanf("%ld%ld",&n,&m);
            ~~^     ~~
            %lld
foo.c:16:12: warning: format '%ld' expects argument of type 'long int', but argument 2 has type 'long long int' [-Wformat=]
  printf("%ld",num);
          ~~^
          %lld
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%ld%ld",&n,&m);
  ^~~~~~~~~~~~~~~~~~~~~

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