我有一个简单的主代码,在调用函数时会给我分段错误。在下面的代码中,我有两个函数,第一个正常工作,但程序没有进入第二个函数,并给我分段错误错误。有什么理由吗?我已经确定了以下内容:
o
和c
不受约束。cn
已正确初始化。cm
和argv
的只读访问权限。另外,它甚至没有输入函数evaluate
以下是代码:
void print_cm(vector<vector<int> > *cm, char* gtf);
void evaluate(vector<vector<int> > *cm, char* gtf);
int main(int argc, char** argv)
{
int o = 2; // It is initialized
int c = 4; // It is initialized
vector<vector<int> > cm; // It is initialized
if (argc>4)
print_cm(&cm, argv[o]);
if (argc>4)
{
cout << argv[c] << endl; // Works
// The following also works
for (int i=0; i<cm.size(); i++)
for (int j=0; j<cm[i].size(); j++)
cout << cm[i][j] << " ";
// The following causes segmentation fault;
evaluate(&cm, argv[c]);
}
return 0;
}
void evaluate(vector<vector<int> > *cm, char* gtf)
{
// Read-only access to cm and gtf
}
void print_cm(vector<vector<int> > *cm, char* gtf)
{
// Read-only access to cm and gtf
}
以下是完整的代码:
#include "includes/Utility.h"
#include "includes/Graph.h"
void print_cm(vector<vector<int> > *cores, char* output);
void evaluate(vector<vector<int> > const *cm, char* gtf);
int main(int argc, char** argv)
{
int g = -1, c = -1, o = -1;
for (int i=1; i<argc-1; i++)
if (argv[i][0]=='-')
{
if (argv[i][1]=='g')
g = i + 1;
else if (argv[i][1]=='c')
c = i + 1;
else if (argv[i][1]=='k')
ki = i + 1;
else if (argv[i][1]=='s')
si = i + 1;
else if (argv[i][1]=='o')
o = i + 1;
}
Graph G;
if (c>0) G.read_input(argv[g], argv[c]);
else G.read_input(argv[g]);
if (ki > 0)
{
int k = atoi(argv[ki]);
cout << k << endl;
}
if (si > 0)
{
int s = atoi(argv[si]);
cout << s << endl;
}
// Find communities
vector<vector<int> > cores;
G.partitioning(&cores);
if (o>0)
print_cm(&cores, argv[o]);
if (c>0)
{
cout << "here" << endl;
for (size_t i=0; i<cores.size(); i++)
for (size_t j=0; j<cores[i].size(); j++)
if (cores.at(i).at(j)<0) cout << "here";
cout << "here" << endl;
evaluate(&cores, argv[c]);
}
}
return 0;
}
void print_cm(vector<vector<int> > *cores, char* output)
{
ofstream out;
out.open(output);
for(size_t i=0; i<(*cores).size(); i++)
{
for(size_t j=0; j<(*cores)[i].size(); j++)
out << (*cores)[i][j] << " ";
out << endl;
}
out.close();
return ;
}
void evaluate(vector<vector<int> > const *cm, char* gtf)
{
// we evaluate precision, recall, F1 and F2
vector<vector<int> > gt;
ifstream in;
char str[100000000];
in.open(gtf);
while(in.getline(str, 100000000))
{
stringstream s;
s << str;
int a;
gt.resize(gt.size()+1);
while (s >> a) gt[gt.size()-1].push_back(a);
}
in.close();
cout << "==================== Evaluation Results ====================" << endl;
int imax = 0;
for(size_t i=0; i<(*cm).size(); i++)
imax = max(imax, *max_element((*cm)[i].begin(), (*cm)[i].end()));
for(size_t i=0; i<gt.size(); i++)
imax = max(imax, *max_element(gt[i].begin(), gt[i].end()));
vector<bool> flag(imax, false);
vector<double> recall((*cm).size(), 0), precision((*cm).size(), 0), f1((*cm).size(), 0), f2((*cm).size(), 0);
int overlap;
double size = 0;
for(size_t i=0; i<(*cm).size(); i++)
{
// evaluate
size += (double) (*cm)[i].size();
for(size_t j=0; j<(*cm)[i].size(); j++)
flag[(*cm)[i][j]] = true;
double p, r, ff1, ff2;
for(size_t j=0; j<gt.size(); j++)
{
overlap = 0;
for(size_t k=0; k<gt[j].size(); k++)
if (flag[gt[j][k]]) overlap++;
p = (double) overlap / (double) (*cm)[i].size();
if (p > precision[i])
precision[i] = p;
r = (double) overlap / (double) gt[j].size();
if (r > recall[i])
recall[i] = r;
ff1 = (double) 2*(p*r)/(p+r);
if (ff1 > f1[i])
f1[i] = ff1;
ff2 = (double) 5*(p*r)/(4*p + r);
if (ff2 > f2[i])
f2[i] = ff2;
}
for(size_t j=0; j<(*cm)[i].size(); j++)
flag[(*cm)[i][j]] = false;
}
double Recall = 0, Precision = 0, F1 = 0, F2 = 0;
for(size_t i=0; i<(*cm).size(); i++)
{
Recall += recall[i];
Precision += precision[i];
F1 += f1[i];
F2 += f2[i];
}
cout << "+--------------+--------------+--------------+--------------+" << endl;
cout << "| " << setiosflags( ios::left ) << setw(10) << "Precision";
cout << " | " << setiosflags( ios::left ) << setw(10) << "Recall";
cout << " | " << setiosflags( ios::left ) << setw(10) << "F1-measure";
cout << " | " << setiosflags( ios::left ) << setw(10) << "F2-measure";
cout << " |" << endl;
cout << "| " << setiosflags( ios::left ) << setw(10) << Precision/(*cm).size() ;
cout << " | " << setiosflags( ios::left ) << setw(10) << Recall/(*cm).size();
cout << " | " << setiosflags( ios::left ) << setw(10) << F1/(*cm).size();
cout << " | " << setiosflags( ios::left ) << setw(10) << F2/(*cm).size();
cout << " |" << endl;
cout << "+--------------+--------------+--------------+--------------+" << endl;
cout << "Number of communities: " << (*cm).size() << endl;
cout << "Average community size: " << size/(*cm).size() << endl;
return ;
}
答案 0 :(得分:2)
char str[100000000];
这是在evaluate
功能中。这是1亿个字节,或者你在堆栈上分配的大约95 MB。
典型的堆栈大小远小于1 MB左右。
除了可能的其他问题之外,这很可能导致堆栈溢出。
进入函数时,堆栈框架会扩展到足以容纳局部变量。一旦使用堆栈然后(写一个默认值)你就会访问无效(非堆栈,谢天谢地)内存。