foo.cc: In function 'int main()':
foo.cc:7:29: warning: unused variable 'c' [-Wunused-variable]
    7 |         int a[100][100], b, c, e, x;
      |                             ^
foo.cc:7:32: warning: unused variable 'e' [-Wunused-variable]
    7 |         int a[100][100], b, c, e, x;
      |                                ^
foo.cc:7:35: warning: unused variable 'x' [-Wunused-variable]
    7 |         int a[100][100], b, c, e, x;
      |                                   ^

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