I don't know anything about C++, I am a C programmer, but I need to compile a tool that is written in C++, and I am stopped with this error:
map.cpp
/usr/lib/gcc-v10.2.0/include/g++-v10/backward/hashtable.h:604:23:
error: no match for call to ‘(const hasher {aka const __gnu_cxx::hash<long long unsigned int>}) (const key_type&)’
604 | { return _M_hash(__key) % __n; }
| ~~~~~~~^~~~~~~
which can be reproduced by the following testing-example:
#include <fstream>
#include <iostream>
#include "map.h"
#include <ext/hash_map>
#include <string>
#include <sstream>
using namespace std;
using __gnu_cxx::hash_multimap;
int nav() {
cout <<"Select from the following options : " << endl <<endl;
cout <<"Search Tweets based on Keyword (Type 1) " <<endl;
cout <<"End Program (Type 2)"<<endl<<endl;
int key =0;
cin >> key;
return key;
}
int main() {
int option = nav();
if (option == 1) {
ifstream readFile("project4.csv");
string tempPop, tempID, tempKey, tempUser, tempDesc;
string tempRead;
hash_multimap<string, Map2 *>map1;
while (readFile != NULL){
// sends to a temp variable
readFile >> tempRead;
for (int i =0; i<400; i++){
//create new object each time
Map2 *mapNode = new Map2(tempPop,tempID,tempKey,tempUser,tempDesc);
//insert each time new object is made
map1.insert(pair<string, Map2 *> (tempKey, mapNode));
} //end for
} //end while
//Navigation through multimap
//first pointer is for first one and second to last hash table value
pair<hash_multimap<string, Map2 *> :: const_iterator,
hash_multimap<string, Map2 *> :: const_iterator> p;
string searchKey = "";
cout << "Please enter the keyword value exactly so we can search the"<<
"available tweets: " <<endl;
cin >> searchKey;
p = map1.equal_range(searchKey);
}
else
return 0;
}
map.h
#ifndef MAP2_H
#define MAP2_H
#include <iostream>
#include <string>
using namespace std;
class Map2 {
public:
Map2(string data1, string data2, string data3, string data4, string data5);
string pop, keyword, user, desc, id;
string get_pop() {return pop;}
string get_key() {return keyword;}
string get_user() {return user;}
string get_desc() {return desc;}
string get_id() {return id;}
void call_Values(int i);
};
Map2:: Map2(string data1, string data2, string data3, string data4, string data5) {
pop = data1;
keyword = data2;
user = data3;
desc = data4;
id = data5;
}
void Map2:: call_Values(int i) {
get_pop();
get_key();
get_user();
get_desc();
get_id();
}
#endif
Anyone has an idea? Workaround? or any doc-suggestion to look at?