foo.cc: In function 'int hwlength(int)':
foo.cc:29:9: warning: variable 'a' set but not used [-Wunused-but-set-variable]
     int a[10],i=0;
         ^
foo.cc: In function 'int main()':
foo.cc:63:13: warning: unused variable 'j' [-Wunused-variable]
     int b,i,j;
             ^

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