#include <iostream>

bool fermat()
{
    constexpr int threshold = 100;
    int a = 1, b = 1, c = 1;
    while(true)
    {
        if( a*a*a + b*b*b == c*c*c )
            return true;
        ++a;
        if(a > threshold)
        {
            a = 1;
            ++b;
        }
        if(b > threshold)
        {
            b = 1;
            ++c;
        }
        if(c > threshold)
            c = 1;
    }
    return false;
}

int main()
{
    using namespace std;
    cout << boolalpha << fermat() << endl;
}

clang++ -std=c++1z -O3 -Wall main.cpp && ./a.out
true