foo.cc: In function 'int main()':
foo.cc:8:12: warning: unused variable 'm' [-Wunused-variable]
    8 |  int i,j,k,m,n,a,b,c;
      |            ^
foo.cc:8:16: warning: unused variable 'a' [-Wunused-variable]
    8 |  int i,j,k,m,n,a,b,c;
      |                ^
foo.cc:8:18: warning: unused variable 'b' [-Wunused-variable]
    8 |  int i,j,k,m,n,a,b,c;
      |                  ^
foo.cc:8:20: warning: unused variable 'c' [-Wunused-variable]
    8 |  int i,j,k,m,n,a,b,c;
      |                    ^

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