Unknown error in inserting values in multimap - c++

Question

I have the following code, where I try to insert values into a multimap of 2 strings, but I keep getting an error that I cannot understand. I've been trying to solve this for hours.
The whole point of the program is to sort the lines of a dictionary based on the automatic sorting of the multimap insertion.
// sort_entries_of_multiple_dictionaries.cpp : This file contains the 'main' function. Program execution begins and ends there.
//
#include <iostream>
#include <fstream>
#include <vector>
#include <map>
#include <string>
#include <algorithm>
#include <iomanip>
#include <sstream>
// Prototypes
int indexDict(std::multimap<std::string, std::string>& dict);
int main()
{
std::multimap<std::string, std::string> dict;
if(indexDict(dict) == 0)
return 0;
}
int indexDict(std::multimap<std::string, std::string>& dict)
{
std::ifstream inputFile{ "output.txt", std::ios::in };
std::string currentDictEntry{};
size_t currentLine{};
if (!inputFile)
{
std::cerr << "input.txt FILE NOT FOUND in the current directory" << std::endl;
system("pause");
return 0;
}
while (std::getline(inputFile, currentDictEntry))
{
//std::cout << currentDictEntry << std::endl; // TO DELETE
std::string currentWord{};
size_t delimiterPos = currentDictEntry.find('\t', 0);
if (delimiterPos == std::string::npos)
std::cerr << "ERROR. Delimiter \"<b>\" not found in line " << currentLine << std::endl;
else
{
//std::cout << "pos of \\t = " << delimiterPos << std::endl; // TO DELETE
for (char& ch : currentDictEntry)
{
if (ch != '\t')
{
currentWord += ch;
}
else
break;
}
std::cout << currentWord /* << '|' */ << std::endl; // TO DELETE
auto value = currentDictEntry.substr(delimiterPos, std::string::npos);
std::cout << "size= " << value.size() << '|' << value << std::endl;
dict.insert( currentWord, currentWord/*, value*/ );
}
if (currentLine == 50) return 0; // TO DELETE
currentLine++;
}
return 1;
}
if (currentLine == 50) return 0; // TO DELETE
currentLine++;
}
return 1;
}
The error I keep getting is:
unary '++': '_Iter' does not define this operator or a conversion to a type acceptable to the predefined operator
illegal indirection

Answer 1

as #Evg said, it accepts a std::pair
dict.insert(std::make_pair(currentWord, value));
if I understand your intention correctly, you don't want to save the \t into your result, so add 1 after delimiterPos to get the correct value:
auto value = currentDictEntry.substr(delimiterPos + 1, std::string::npos);
test run. output.txt:
4 d
1 a
2 b
3 c
0
output:
"0" - ""
"1" - "a"
"2" - "b"
"3" - "c"
"4" - "d"
full code:
#include <iostream>
#include <fstream>
#include <map>
#include <string>
#include <iomanip>
#include <sstream>
// Prototypes
int indexDict(std::multimap<std::string, std::string>& dict);
int main()
{
std::multimap<std::string, std::string> dict;
if (indexDict(dict) == 0)
return 0;
for (auto& i : dict) {
std::cout << "\"" << i.first << "\" - \"" << i.second << "\"\n";
}
}
int indexDict(std::multimap<std::string, std::string>& dict)
{
std::ifstream inputFile{ "output.txt", std::ios::in };
std::string currentDictEntry{};
size_t currentLine{};
if (!inputFile)
{
std::cerr << "output.txt FILE NOT FOUND in the current directory" << std::endl;
system("pause");
return 0;
}
while (std::getline(inputFile, currentDictEntry))
{
//std::cout << currentDictEntry << std::endl; // TO DELETE
std::string currentWord{};
size_t delimiterPos = currentDictEntry.find('\t', 0);
if (delimiterPos == std::string::npos)
std::cerr << "ERROR. Delimiter \"<b>\" not found in line " << currentLine << std::endl;
else
{
//std::cout << "pos of \\t = " << delimiterPos << std::endl; // TO DELETE
for (char& ch : currentDictEntry)
{
if (ch != '\t')
{
currentWord += ch;
}
else
break;
}
std::cout << currentWord /* << '|' */ << std::endl; // TO DELETE
auto value = currentDictEntry.substr(delimiterPos + 1, std::string::npos);
std::cout << "size= " << value.size() << '|' << value << std::endl;
dict.insert(std::make_pair(currentWord, value));
}
if (currentLine == 50) return 0; // TO DELETE
currentLine++;
}
return 1;
}
small mistakes in your code: you don't need <algorithm> and <vector>. also your error message said input.txt instead of output.txt.

Answer 2

I Change dict.insert( currentWord, currentWord/*, value*/ ); To dict.insert({ currentWord,currentWord }); and error Has solved