foo.cc: In function 'int main()':
foo.cc:30:12: warning: unused variable 'y' [-Wunused-variable]
   30 |  int x=100,y=0,a[10],s=0;
      |            ^
foo.cc:30:16: warning: unused variable 'a' [-Wunused-variable]
   30 |  int x=100,y=0,a[10],s=0;
      |                ^
foo.cc:30:22: warning: unused variable 's' [-Wunused-variable]
   30 |  int x=100,y=0,a[10],s=0;
      |                      ^

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