/in/foo.cc: In function 'int cmp(man, man)':
/in/foo.cc:7:14: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  if(a.sc=b.sc)return a.id<b.id;
              ^
/in/foo.cc: In function 'void merge()':
/in/foo.cc:13:10: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
  while(xa<n&xb<n){
        ~~^~