foo.cc: In function 'int main()':
foo.cc:11:13: error: redeclaration of 'int a'
   11 |         int a,b,c;
      |             ^
foo.cc:5:9: note: 'int a' previously declared here
    5 |     int a,b,c;
      |         ^
foo.cc:11:15: error: redeclaration of 'int b'
   11 |         int a,b,c;
      |               ^
foo.cc:5:11: note: 'int b' previously declared here
    5 |     int a,b,c;
      |           ^
foo.cc:11:17: error: redeclaration of 'int c'
   11 |         int a,b,c;
      |                 ^
foo.cc:5:13: note: 'int c' previously declared here
    5 |     int a,b,c;
      |             ^
foo.cc:17:13: error: redeclaration of 'int a'
   17 |         int a,b,c;
      |             ^
foo.cc:5:9: note: 'int a' previously declared here
    5 |     int a,b,c;
      |         ^
foo.cc:17:15: error: redeclaration of 'int b'
   17 |         int a,b,c;
      |               ^
foo.cc:5:11: note: 'int b' previously declared here
    5 |     int a,b,c;
      |           ^
foo.cc:17:17: error: redeclaration of 'int c'
   17 |         int a,b,c;
      |                 ^
foo.cc:5:13: note: 'int c' previously declared here
    5 |     int a,b,c;
      |             ^

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