我无法输出列表矢量:
class index_table {
public:
index_table() { table.resize(128);}
void insert(string &, int );
private:
class entry
{
public:
string word;
vector <int> line;
};
vector< list <entry> > table;
};
我已经知道它会填满:
int main ()
{
index_table table;
string word,
int num = 5; //this is going to a random number. 5 is a temp. place holder.
while (cin >> word)
table.insert(word, num);
}
但如何输出呢?我尝试了很多不同的方法,但很多方法都给了我错误 我是否必须超载操作员?我不完全确定我将如何做到这一点。
答案 0 :(得分:3)
假设您确实有充分的理由使用std::vector< std::list<entry> >
,那么根据给定的结构,单词的打印可能如下所示:
class index_table {
public:
void print() {
for (size_t i = 0; i < table.size(); ++i) {
std::list<entry>::iterator li;
for (li = table[i].begin(); li != table[i].end(); ++li)
std::cout << li->word << " ";
}
}
...
private:
std::vector< std::list<entry> > table;
...
};
答案 1 :(得分:1)
如果您的编译器支持C ++ 11,则可以使用两个基于范围的嵌套for循环。查看函数void index_table::dump()
。
// Output function
void index_table::dump() {
for (list<entry> &le : table) {
for (entry &e : le) {
e.dump();
}
}
}
我还在条目类中创建了一个函数dump()
,它输出两个变量的内容,现在变为私有。
class index_table {
public:
index_table() {
table.resize(128);
}
void insert (int,string&,int);
void dump();
private:
class entry {
private:
string word;
int value;
public:
entry (string word, int value) {
this->word = word;
this->value = value;
}
void dump() {
cout << "Word/value is: " << word << "/" << value << endl;
}
};
vector< list <entry> > table;
};
void index_table::insert(int c, string &key, int value) {
//void index_table::insert(string &key, int value) {
entry obj(key, value);
table[c].push_back(obj);
}
// Output function
void index_table::dump() {
for (list<entry> &le : table) {
for (entry &e : le) {
e.dump();
}
}
}
int main (int argc, char **argv) {
index_table mytable;
string a = "String 0-A";
string b = "String 0-B";
string c = "String 1-A";
string d = "String 1-B";
string e = "String 6-A";
string f = "String 6-B";
mytable.insert(0, a, 1);
mytable.insert(0, b, 2);
mytable.insert(1, c, 3);
mytable.insert(1, d, 4);
mytable.insert(6, e, 3);
mytable.insert(6, f, 4);
mytable.dump();
}
节目输出:
Word/value is: String 0-A/1
Word/value is: String 0-B/2
Word/value is: String 1-A/3
Word/value is: String 1-B/4
Word/value is: String 6-A/3
Word/value is: String 6-B/4
PS:我也改变了你的代码,使其更容易运行我的测试。
答案 2 :(得分:0)
//This is the simple solution for outputting vector of lists.
#include <bits/stdc++.h>
using namespace std;
main()
{
vector<list<int>> my_vector; //creating vector of lists;
list<int> my_list;
for(int i = 0; i < 5; i++)
my_list.push_back(i);
my_vector.push_back(my_list); // pushing a list y to a vector
for (vector<list<int>>::iterator it = my_vector.begin(); it != my_vector.end(); ++it)
for (list<int>::iterator it2 = it->begin(); it2 != it->end(); ++it2)
cout << *it2 << ", ";
}