C ++随机播放向量 [英] C++ Shuffle Vector
问题描述
我看到其他线程,但没有似乎回答我的问题。我试图在向量上使用 shuffle()
函数,但我不断收到错误:
deck_of_cards.cpp:34:5:错误:没有匹配函数调用'shuffle'
pre>
shuffle(deck.begin(),deck.end(),std :: default_random_engine种子));
^ ~~~~~~
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/algorithm:3049:10 :note:候选函数[with
_RandomAccessIterator = std :: __ 1 :: __ wrap_iter< Card *>,_UniformRandomNumberGenerator = std :: __ 1 :: linear_congruential_engine< unsigned int,48271,0,
2147483647>不可行:期望第三个参数的l值
void shuffle(_RandomAccessIterator __first,_RandomAccessIterator __last,
^
生成错误
我使用clang ++作为我的编译器,这是我的代码是抛出的错误:
void DeckOfCards :: shuffleDeck()
{
seed = std :: chrono :: system_clock :: now()。time_since_epoch()。count();
shuffle(deck.begin(),deck.end(),std :: default_random_engine(seed));
}
我在程序中有所有正确的
#includes
我是C ++的新手,这基本上是一个Java程序,有我试图转换为C ++。任何帮助将不胜感激!解决方案编译器告诉你它期望一个左值ar第三个参数,你给它一个右值的临时对象)。
尝试此操作:
auto gen = std :: default_random_engine种子);
shuffle(deck.begin(),deck.end(),gen);
请注意,
std :: shuffle
应接受一个右值作为第三个参数,因此符合标准的实现将接受您的代码。I have seen other threads on this but none seem to answer my question. I'm trying to use the
shuffle()
function on a vector but I keep getting an error:deck_of_cards.cpp:34:5: error: no matching function for call to 'shuffle' shuffle (deck.begin(), deck.end(), std::default_random_engine(seed)); ^~~~~~~ /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/c++/v1/algorithm:3049:10: note: candidate function [with _RandomAccessIterator = std::__1::__wrap_iter<Card *>, _UniformRandomNumberGenerator = std::__1::linear_congruential_engine<unsigned int, 48271, 0, 2147483647>] not viable: expects an l-value for 3rd argument void shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last, ^ 1 error generated.
I'm using clang++ as my compiler and this is my code that is throwing the error:
void DeckOfCards::shuffleDeck() { seed = std::chrono::system_clock::now().time_since_epoch().count(); shuffle (deck.begin(), deck.end(), std::default_random_engine(seed)); }
I do have all the correct
#includes
in my program. I'm fairly new to C++ and this is basically a Java program that I have that I'm trying to convert to C++. Any help would be appreciated!解决方案The compiler is telling you that it expects an lvalue ar third parameter, and you are giving it an rvalue (in the form of a temporary object).
Try this:
auto gen = std::default_random_engine(seed); shuffle (deck.begin(), deck.end(), gen);
Note that
std::shuffle
should accept an rvalue as third parameter, so a standards-compliant implementation would have accepted your code.这篇关于C ++随机播放向量的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!