foo.c:3:1: error: unknown type name 'using'
    3 | using namespace std;
      | ^~~~~
foo.c:3:17: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'std'
    3 | using namespace std;
      |                 ^~~
foo.c: In function 'main':
foo.c:7:2: error: unknown type name 'bool'
    7 |  bool a[10005];
      |  ^~~~
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d%d",&n,&m);
      |  ^~~~~~~~~~~~~~~~~~~
foo.c:12:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   12 |   scanf("%d%d",&b,&c);
      |   ^~~~~~~~~~~~~~~~~~~

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