冲突std :: set和ntl :: vec_zz

Question

我正在尝试使用std ::设置从ntl-library定义的任意长度的整数矢量，并且出于某种原因它不起作用。它与库定义的ZZ整数完全很好：

#include <NTL/ZZ.h>
#include <NTL/vec_ZZ.h>
#include <set>

NTL_CLIENT

int main(void){


    std::set<ZZ> foo;
    foo.insert(to_ZZ(1)); //works without problems

    std::set<vec_ZZ> vectorFoo;
    vec_ZZ vec;
    vectorFoo.insert(vec);  //causes compiler to crash

    return 0;
}

.

有谁知道为什么第一个插入工作和第二个没有？

Answer 1

std::set<T> is ordered by std::less<T>, which defaults to bool operator<(T,T). ZZ does define a proper operator< (they're ordered) but vec_ZZ doesn't. In fact, most NTL classes don't, not even ZZ_p. Therefore std::set<ZZ_p> is equally invalid.