foo.cpp:5:11: error: expected ';' at end of member declaration
  unsigned mark_ assess;//班级评定成绩 
           ^
foo.cpp:5:17: error: 'assess' does not name a type
  unsigned mark_ assess;//班级评定成绩 
                 ^
foo.cpp: In function 'int main()':
foo.cpp:18:64: error: 'struct Student' has no member named 'mark_assess'
   std::cin>>student[i].name>>student[i].mark_final>>student[i].mark_assess>>student[i].leader>>student[i].western>>student[i].paper;
                                                                ^
foo.cpp:19:17: error: 'struct Student' has no member named 'mark_assess'
   if(student[i].mark_assess>80)
                 ^
foo.cpp:23:26: error: 'Y' was not declared in this scope
    if(student[i].leader==Y)
                          ^
foo.cpp:28:55: error: 'Y' was not declared in this scope
   if((student[i].mark_final>85)&&(student[i].western==Y))
                                                       ^
foo.cpp:33:6: error: 'i' was not declared in this scope
  for(i=0,temp=student[0].reward;i<N;i++){
      ^