[ntl] Compiling error

[mxprm]

Hello everyone,

When I compile this code and "g++ file.cpp -o file -lntl" I have no problem
(I say this because I want to show that NTL is already installed)

#include<iostream>
#include<NTL/ZZ.h>
using namespace std;
using namespace NTL;

int main(){
    return 0;
}

But when I added this line in my function main:

ZZ a;

this error displayed me.

/tmp/ccuCJ2il.o: at the function`NTL::ZZ::~ZZ()':
file.cpp:(.text._ZN3NTL2ZZD2Ev[_ZN3NTL2ZZD5Ev]+0x14): not
reference`_ntl_zfree' without define
collect2: error: ld returned 1 exit status

Please I need help with this. I have no idea why is this happening.
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