foo.c: In function 'main':
foo.c:6:3: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'cin'
   cin<<a;
   ^~~
foo.c:6:3: error: 'cin' undeclared (first use in this function); did you mean 'main'?
   cin<<a;
   ^~~
   main
foo.c:6:3: note: each undeclared identifier is reported only once for each function it appears in
foo.c:6:8: error: 'a' undeclared (first use in this function)
   cin<<a;
        ^

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