foo.cc: In function 'int main()':
foo.cc:7:13: warning: unused variable 'b' [-Wunused-variable]
    7 |     int n,a,b,c,s1,s2,s3,i;
      |             ^
foo.cc:7:15: warning: unused variable 'c' [-Wunused-variable]
    7 |     int n,a,b,c,s1,s2,s3,i;
      |               ^
foo.cc:7:20: warning: unused variable 's2' [-Wunused-variable]
    7 |     int n,a,b,c,s1,s2,s3,i;
      |                    ^~
foo.cc:7:23: warning: unused variable 's3' [-Wunused-variable]
    7 |     int n,a,b,c,s1,s2,s3,i;
      |                       ^~

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