foo.cc: In function 'int main()':
foo.cc:89:8: warning: unused variable 'b' [-Wunused-variable]
   89 |  int a,b=0,c,d,i,j;
      |        ^
foo.cc:89:12: warning: unused variable 'c' [-Wunused-variable]
   89 |  int a,b=0,c,d,i,j;
      |            ^
foo.cc:89:14: warning: unused variable 'd' [-Wunused-variable]
   89 |  int a,b=0,c,d,i,j;
      |              ^
foo.cc:89:18: warning: unused variable 'j' [-Wunused-variable]
   89 |  int a,b=0,c,d,i,j;
      |                  ^

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