Question

Implement a C++ map to store data in a file, such as any .dat or .txt file filled with data. The data should be loaded to map from the data file.

Answer 1

#include<iostream> //for cout
#include<fstream> //for ifstream
#include<map> //for map
#include<iterator> //for iterator
using namespace std;

//main function
int main()
{
map<int,int> m; //declared variable of map
ifstream in; //declared in stream
in.open("input.txt"); //opens input.txt file
int x,y;
if(in==NULL){ //if file fails to open then prints message and terminates program
cout<<"Error occurred while opening file";
return -1;
}
while(in>>x>>y) //reads values into x and y
{
m.insert(pair<int,int>(x,y)); //inserts values accordingly into map
}
//creates and iterator for map
map<int,int>::iterator it = m.begin();
while(it!=m.end()){ //iterates till end of map and prints the values in map
cout<<it->first<<" "<<it->second<<endl;
it++;
}

return 0; //terminates the program
}

//output screenshot

//input.txt screenshot

//any query, post in the comment section