/in/foo.cc: In function 'int main()':
/in/foo.cc:18:14: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    if(x=false)
              ^
/in/foo.cc:21:12: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   if(x=true)
            ^
/in/foo.cc:5:10: warning: unused variable 'j' [-Wunused-variable]
  int n,i,j;
          ^