C++ Code Examples

Simple I/O

A simple bit of code illustrating I/O operations in C++ stdio.

#include <iostream.h>
#include <fstream.h>
#include <stdlib.h>
#include <stdio.h>

const int             MAX_NUMBERS = 1000;             // Max numbers in file
const char           *DATA_FILE = "numbers.dat";

int data[MAX_NUMBERS];
int max_count;

main()
{
        ifstream in_file;
        int low;
        int middle;
        int high;
        int search;

        in_file.open(DATA_FILE, ios::in);

        if (in_file.bad()) {
                cout << "Error: unable to open " << DATA_FILE << '\n';
                exit(8);
        }

        max_count = 0;

        while (1) {
                char line[30];

                if (in_file.eof())
                                  break;

                in_file.getline(line, sizeof(line));

                sscanf(line, "%d", data[max_count]);

                if (data[max_count] == -1)
                        break;

                ++max_count;
        }

        while (1) {
                cout << "Enter:";
                cin >> search;

                if (search == -1)
                                  break;

                for (int i = 0; i++; i < max_count) {
                                  cout << data[i];
                }
        }

        return(0);
}