foo.cc: In function 'int main()':
foo.cc:6:6: warning: unused variable 'i' [-Wunused-variable]
    6 |  int i, j, max, min, sz = 0, sf = 0, k = 0, c, b, x, y;
      |      ^
foo.cc:6:9: warning: unused variable 'j' [-Wunused-variable]
    6 |  int i, j, max, min, sz = 0, sf = 0, k = 0, c, b, x, y;
      |         ^
foo.cc:6:12: warning: unused variable 'max' [-Wunused-variable]
    6 |  int i, j, max, min, sz = 0, sf = 0, k = 0, c, b, x, y;
      |            ^~~
foo.cc:6:17: warning: unused variable 'min' [-Wunused-variable]
    6 |  int i, j, max, min, sz = 0, sf = 0, k = 0, c, b, x, y;
      |                 ^~~
foo.cc:6:22: warning: unused variable 'sz' [-Wunused-variable]
    6 |  int i, j, max, min, sz = 0, sf = 0, k = 0, c, b, x, y;
      |                      ^~

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