hw11_p1.cpp

#include <iostream>
#include <fstream>
#include <cstdlib>
#include <iomanip>
#include <vector>
#include <algorithm>
#include <string>

using namespace std;

int main(){
    int i, j, k, n = 0, n1, n2, n3, pos;
    std::vector<int> array1, array2, array3;

    std::string inname1 = "HW11F1.txt";
    std::string inname2 = "HW11F2.txt";
    std::string inname3 = "output.txt";

    cout << "Filenames are restricted to 12 characters" << endl;

    cout << "Enter the first of two input file names: ";
    cin >> inname1;
    cout << endl;

    cout << "Now a second input file name: ";
    cin >> inname2;
    cout << endl;

    cout << "Enter the output file name." << endl
     << "WARNING: ANY EXISTING FILE WITH THIS NAME WILL BE ERASED.";
    cin >> inname3; cout << endl;

    std::ifstream infile1 (inname1.c_str());
    std::ifstream infile2 (inname2.c_str());

    if (!infile1 or !infile2) {
        cout << "There was a problem opening a file.";
        return 0;
    }

    pos = 0; i = 0;
    while (infile1 >> i) {
        array1.resize(pos+1);
        array1[pos] = i;
        pos++;
    }

    pos = 0; i = 0;
    while (infile2 >> i) {
        array2.resize(pos+1);
        array2[pos] = i;
        pos++;
    }

    n1 = array1.size();
    n2 = array2.size();
    n3 = n1 + n2;
    array3.resize(n3);

    i = 0; j = 0; k = 0;
    while (i < n1 && j < n2) {
        if (array1[i] <= array2[j]) {
            array3[k++] = array1[i++];
        } else {
            array3[k++] = array2[j++];
        }
    }

    while (i < n1) array3[k++] = array1[i++];
    while (j < n2) array3[k++] = array2[j++];

    std::ofstream outfile (inname3.c_str());
    outfile.open(inname3.c_str());

    i = 0;
    while(i<n3){
        outfile << array3[i] << endl;
        i++;
    }

    cout << "Contents of file " << infile1 << " are: ";
    for(i = 0; i < array1.size(); i++){
        cout << array1[i] << endl;
    }
    cout << "Contents of file " << infile2 << " are: ";
    for(i = 0; i < array2.size(); i++){
        cout << array2[i] << endl;
    }
    cout << "Contents of merged file, " << outfile << " are: ";
    for(i = 0; i < array3.size(); i++){
        cout << array3[i] << endl;
    }

    infile1.close();
    infile2.close();
    outfile.close();
    return 0;
}