/in/foo.cc: In function 'int main()':
/in/foo.cc:23:8: warning: left operand of comma operator has no effect [-Wunused-value]
  for(i,k;i<=j&&k>=1;m--)
        ^
/in/foo.cc:23:9: warning: right operand of comma operator has no effect [-Wunused-value]
  for(i,k;i<=j&&k>=1;m--)
         ^