/in/foo.cc: In function 'int main()':
/in/foo.cc:13:18: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    if(a[j] = a[i])
                  ^
/in/foo.cc:21:12: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   if(a != -1)
            ^