Question

C++ programming question

1. Write a program that will read input from a text file called "theNumbers.txt" (you will have to provide your own when debugging). The text file that is to be opened is formatted a certain way, namely, there is always one integer, one character (representing an operation), another integer, and then a new line character, with spaces between each item. A sample text file is provided below.

theNumbers.txt

144 + 26

3 * 18

88 / 4

22 – 8

16 / 2

20 * 20

-Your Program should read in all items, compute the answer to each expression (any decimals should be rounded to the nearest tenth), and output the answers to an output file of the user's choosing. The formatting of the output is that there is a set width of 10 characters for each answer, left aligned, with a new line character every 3 answers. A sample “answers.txt” is provided below. (not drawn to scale)

answers.txt

17000      54      22

14               8            400

-You may assume that the name of the text file that will be outputted to is always 20 characters or less.

-You may assume that there are only 4 possible operations ( + - *   /), add, subtract, multiply, and decimal division, and that no other characters will show up as the middle symbol.

- Appropriate error messages should be displayed if the file cannot be opened.

- Extra Credit: The answers in the output file ONLY show a decimal if the answer is not a whole number answer.

Answer 1

If you have any doubts, please give me comment...

#include<iostream>

#include<iomanip>

#include<fstream>

using namespace std;

int main(){

    int num1, num2, n;

double result;

    char op;

    ifstream inFile;

    inFile.open("theNumbers.txt");

    if(inFile.fail()){

        cout<<"Unable to open file"<<endl;

        return -1;

    }

    ofstream outFile;

    outFile.open("answers.txt");

    n = 1;

    while(!inFile.eof()){

        inFile>>num1>>op>>num2;

        if(op=='+')

            result = num1 + num2;

        else if(op=='-')

            result = num1 - num2;

        else if(op=='*')

            result = num1 * num2;

        else

            result = (double)num1 / num2;

        outFile<<setw(10)<<left<<result;

        if(n%3==0)

            outFile<<endl;

        n++;

    }

    cout<<"Successfully saved into answers.txt"<<endl;

    outFile.close();

    inFile.close();

    return 0;

}