假设
b = ["good ", "bad "]
a = ["apple","mango"]
then output = ["good apple","good mango","bad apple","bad mango"]
我知道这可以用嵌套的for循环来完成,但是使用C++ STL是否有一些优雅的衬里呢？
ANSI 颜色代码的范围是什么。在下面的代码中，所有内容都是蓝色的。我只想要蓝色的“编译成功”。这里有像关闭标签（例如在 HTML 中）这样的东西吗？
cout<<"\n\e[0;34mCompiled Successfully!!\n";
sym_table.render();
cout<<"\n\nAll variables according to sizes:\n";
for(auto el: addr_table){
cout<<el.first<<" "<<el.second<<endl;
}
I am trying to write a function such that f<T>(args..) returns the first parameter of type T.
The following program seems to always select the first specialization thus printing 97 (ASCII code of 'a'). Though the second one wouldn't require converting char to int. Could someone please explain the behavior?
I am new to SFINAE and meta-programming.
#include <iostream>
using namespace std;
template <typename T, typename ...Ts>
T f(T a, Ts... args) {
return a;
}
template …如果我有一个三元组列表，我想要三个单独的列表。有没有比这更好的方法：
(listA, listB, listC) = (list.map(_._1), list.map(_._2). list.map(_._3))
哪个可以用于任何 n 元组？
编辑： 虽然我在写这个问题时不知道存在三个 unzip3，但有没有办法编写一个函数来获取一般的 n 个列表？
utop # [1;2];;
- : int list = [1; 2]
utop # 1::2::[];;
- : int list = [1; 2]
utop # 1::2::[] == [1;2];;
- : bool = false
虽然单独评估的两个表达式看起来相同,但为什么OCaml相等函数返回false？