/*
   testarr14.cpp
   CIS 150
   06/23/2005
   David Klick

   This program demonstrates how to search for information
   in parallel arrays, with the array data coming from a
   data file.
*/

#include <iostream>
#include <iomanip>
#include <fstream>
using std::cout;
using std::cin;
using std::setw;
using std::left;
using std::ifstream;

const int ARRAY_SIZE = 100;  // must leave more space than needed

int find(int id[], int length, int idnum);

int main(void) {
   int n, pos;
   int numrecs = 0;  // number of array elements being used
   
   // declare arrays of names and IDs
   char names[ARRAY_SIZE][40];
   int id[ARRAY_SIZE];

   // open file containing name and ID data
   ifstream infile("arraydata.txt");
   if (!infile) {
      cout << "Error: Could not open input file\n";
      return 1;
   }
   
   // load arrays from file
   infile >> id[0];
   while (infile && numrecs<ARRAY_SIZE) {
      infile.getline(names[numrecs], 40, '\n');
      numrecs++;
      if (numrecs < ARRAY_SIZE) {
         infile >> id[numrecs];
      }
   }
   infile.close();
      
   // loop until user chooses to exit
   do {
   
      // find out which ID # the user wants to display
      cout << "Find which user id? (-999 to exit) ";
      cin >> n;
   
      // display desired name if user didn't choose to exit
      if (n != -999) {
         pos = find(id, ARRAY_SIZE, n);
         if (pos == -1) {
            cout << "Error: ID number not found\n";
         } else {
            // display names associated with ID #
            cout << setw(3) << n << ": " << names[pos] << '\n';
         }
      }
   } while (n != -999);
   
   return 0;
}

int find(int id[], int length, int idnum) {
   int i;
   for (i=0; i<length; i++) {
      // if found, then return position in array
      if (idnum == id[i]) return i;
   }
   
   // not found, so return -1
   return -1;
}