foo.cc: In function 'int main()':
foo.cc:9:10: warning: suggest parentheses around comparison in operand of '|' [-Wparentheses]
     if (z>=qi|z<0) 
         ~^~~~
foo.cc:7:11: warning: unused variable 'v' [-Wunused-variable]
     int z,v;           
           ^

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