我正在尝试实现 a radix sort
,并且此代码会产生内存故障:
(free(): invalid next size (fast))
代码如下:
unsigned int * radix(unsigned int *x,int n, int g,bool verbose)
{
int elem_size = sizeof(unsigned int)*8;
int mask = ((1<<g)-1);
float num_rounds= ((float)elem_size/(float)g);
int B = 1 << g; // 2^g BTW
vector<unsigned int> buckets[B];
// begin radix sort
for( unsigned int round=0 ; round<num_rounds ; ++round)
{
// count
for(int elem=0 ; elem<n ; ++elem)
{
// calculate the bucket number:
unsigned int const bucket_num = ( x[elem] >> g*round) & mask;
---> buckets[bucket_num].push_back(x[elem]);
}
// more stuff
}
return x;
}
GDB
指出错误在 push_back 内,但elem
总是小于n
(n
的大小在哪里x[]
)。所以,我认为它只能在bucket_num
. 然而,就在它崩溃之前GDB
给了我他们的价值观:
Breakpoint 1, radix (x=0x604010, n=50, g=4, verbose=true) at radix.mpi.seq.cpp:38 38 buckets[bucket_num].push_back(x[elem]); 2: B = 16 1: bucket_num = 2
有任何想法吗?