Question

int delta[4][2] = {{0,1},{1,0},{0,-1},{-1,0}};
random_shuffle(&delta[0],&delta[4]);

编译错误：

/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h: In function 'void std::swap(_Tp&, _Tp&) [with _Tp = int [2]]':
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:127:   instantiated from 'static void std::__iter_swap<true>::iter_swap(_ForwardIterator1, _ForwardIterator2) [with _ForwardIterator1 = int (*)[2], _ForwardIterator2 = int (*)[2]]'
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:163:   instantiated from 'void std::iter_swap(_ForwardIterator1, _ForwardIterator2) [with _ForwardIterator1 = int (*)[2], _ForwardIterator2 = int (*)[2]]'
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algo.h:1906:   instantiated from 'void std::random_shuffle(_RandomAccessIterator, _RandomAccessIterator) [with _RandomAccessIterator = int (*)[2]]'main.cpp:150:   instantiated from here
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:97: error: array must be initialized with a brace-enclosed initializer
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:98: error:    ISO C++ forbids assignment of arrays
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:99: error: ISO C++ forbids assignment of arrays

在Windows g ++上编译相同的代码。

Answer 1

std::random_shuffle通过交换工作。交换（通常）需要分配。但阵列不可分配。在C ++ 11中，对于不使用直接赋值的数组，存在std::swap的特化。因此，您需要启用C ++ 11才能使代码正常工作。添加编译器选项-std=c++11（如果您的gcc版本支持它）。

random_shuffle（）适用于windows，但不能在linux上编译

1 个答案: