<algorithm> 에 sort 함수를 사용하려고 하는데요

솔라리스에서 컴파일을 하고 있는데 안되거든요;
g++은
bash-3.00# g++ -v
Reading specs from /usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/specs
Configured with: ../configure --with-as=/usr/ccs/bin/as --with-ld=/usr/ccs/bin/ld --enable-shared --enable-languages=c,c++,f77
Thread model: posix
gcc version 3.4.6
이렇고요
컴파일하면 에러내용이
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h: In function `const _Tp& std::__median(const _Tp&, const _Tp&, const _Tp&, _Compare) [with _Tp = int, _Compare = bool (*)(int&, int&)]':
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:2519: instantiated from `void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Size = int, _Compare = bool (*)(int&, int&)]'
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:2589: instantiated from `void std::sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator > >, _Compare = bool (*)(int&, int&)]'
Test.cpp:57: instantiated from here
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:124: error: invalid initialization of reference of type 'int&' from expression of type 'const int'
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:125: error: invalid initialization of reference of type 'int&' from expression of type 'const int'
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:127: error: invalid initialization of reference of type 'int&' from expression of type 'const int'
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:131: error: invalid initialization of reference of type 'int&' from expression of type 'const int'
/usr/local/lib/gcc/i386-pc-solaris2.10/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:133: error: invalid initialization of reference of type 'int&' from expression of type 'const int'
이렇고요
소스는 간단한 성적받아서 sort하는거에요
#include

#include

#include

using namespace std;

bool isBigger( int& a, int& b);

int main()

{

int num;

vector It;//리스트 객체 생성

while(true)

{

cout << "성적을 입력하세요 (-1을 입력하면 종료) : ";

cin >> num;

if(num == -1)

break;

if(num < 0 || num > 100)

{

cout << "0에서 100사이의 값을 입력하세요.\n";

continue;

}

It.push_back(num);//리스트에 데이터 추가

}

int sum = 0;

sort( It.begin(), It.end(), isBigger);

//It.sort();//리스트의 항목을 오름차순으로 정렬

cout << "입력된 점수(오름차순) : ";

vector::iterator it;

for(it = It.begin(); it != It.end(); ++it)

{

sum += (*it);

cout << (*it) << " ";

}

double average = (double) sum / It.size();

cout<<"\n학생수 : " << It.size() << "명, 평균 : " << average << "점\n";

return 0;

}

bool isBigger( int& a, int& b)

{

if( a>= b)

{

return true;

}

else

{

return false;

}

}