Question

C++ need help with vector. I have a text file and input it's content into a struct that holds an array for each entry as a string type.

for example:

struct container{

string ID[10000];

string anotherID[10000];

}

in the text file there is a huge list that looks something like this:
1 abc

3 xyz

1 abc

1 xyz

How can I use a vector to sort these so I can get an output like

ID: 1 and anotherID: abc found 2 time(s)

ID: 1 and anotherID: xyz found 1 time(s)

ID: 3 and anotherID: xyz found 1 time(s)

Answer 1

The solution for the above question is given below with the screenshot of output.
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I have kept the logic simple and output as per the question.

If there is anything else do let me know in comments

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id.txt

1 abc
3 xyz
1 abc
1 xyz

--------------- CODE TO COPY -----------------------------------------------------------------------

main.cpp

#include<iostream>
#include<fstream>
#include<vector>
using namespace std;

struct container{
  
  string ID[10000];
  string anotherID[10000];
  int times[10000];

};

void sort( struct container *con, int count){
  
   int i, j;
   for (i = 0; i < count-1; i++)      
 
       // Last i elements are already in place   
       for (j = 0; j < count-i-1; j++) {
         
            if ( con->ID[j] > con->ID[j+1] )
            {
              string id;
              string anotherID;
              int times;
              
              id = con->ID[j];
              anotherID = con->anotherID[j];
              times = con->times[j];
              
              con->ID[j] = con->ID[j + 1] ;
              con->anotherID[j] = con->anotherID[j + 1];
              con->times[j] = con->times[j + 1];
              
              con->ID[j + 1] = id;
              con->anotherID[j + 1] = anotherID;
              con->times[j + 1] = times;
            }
       }
}

int main() {
  
  container con;
  int count = 0;
  
  ifstream in;
  in.open("id.txt");
  
  if ( in.fail() ) {
    cerr << "Error : cannot open file." << endl;
    return 1;
  }
  
  // reading data from file 
  
  while ( in.eof() == false ){
    
    string id;
    string anotherID;
    int i = 0, found = 0;
    
    in >> id >> anotherID;
    
    // if id alreaky in array increase times
    for ( i = 0; i < count; i++ )
    {
      if ( con.ID[i] == id )
        if ( con.anotherID[i] == anotherID ){
          con.times[i] = con.times[i] + 1;
          found = 1;
        }
    }
    
    // if ad not found add it to list
    if ( i >= count ){
      con.ID[count] = id;
      con.anotherID[count] = anotherID;
      con.times[count] = 1;
    }
    
    if ( ! found )
      count++;
  }
  
  sort( &con, count);
  
  for ( int i = 0; i < count; i++ )
    cout  << "ID: " << con.ID[i] 
          << " and anotherID: "
          << con.anotherID[i] 
          << " found "
          << con.times[i] 
          << " time(s)" << endl;
  
  
  in.close();
  return 0;
}

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Output :

gcc version 4.6.3 ID: 1 and anotherID: abc found 2 time(s) ID: 1 and anotherID: xyz found 1 time(s) ID: 3 and anotherID: xyz found 1 time(s)