foo.c:1:1: error: unknown type name 'importmath'
    1 | importmath
      | ^~~~~~~~~~
foo.c:2:3: error: expected expression before 'int'
    2 | a=int(input())
      |   ^~~
foo.c:5:10: error: stray '\' in program
    5 | p-(a+b+c)\2
      |          ^

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