Question

I am confused how to make program like convert binary to decimal and octal to decimal using array in c++.

This is question as below one.

Your program must have at least two significant user defined functions, each using C++ arrays. Programs done using only main function, and done without using arrays, will get no credit. The program you will submit will have a menu driven system as below:

Caution! No validation is done on numbers entered. They must conform to required input form.
******Main Menu******
1. Convert binary to decimal:

2. Convert Octal to decimal: 3. Exit:
1
Enter the binary number :10101

Original binary Number: 10101

Its decimal conversion:21
Caution! No validation is done on numbers entered. They must conform to required input form.
******Main Menu******
1. Convert binary to decimal:
2. Convert Octal to decimal:
3. Exit:

Enter the octal number :177
Original octal Number: 177

Its decimal conversion:127
Caution! No validation is done on numbers entered. They must conform to required input form.
******Main Menu******
1. Convert binary to decimal:
2. Convert Octal to decimal:
3. Exit:
3

And I should use #include <fstream> to exit the program.

Answer 1

CODE:

#include <iostream>

#include <cmath>

#include <stdlib.h>

using namespace std;

// function to convert bin to decimal

int binToDecimal(int arr[],int n)

{

  int sum=0;

  int count=0;

  for(int i=n-1;i>=0;i--){

    // if arr of i is 1 then multiply it with power of 2 starting with 0

    // and add it in sum

    if(arr[i]==1)

        sum+=pow(2,count);

    count++;

  }

  return sum;

}

// function to convert oct to decimal

int octToDecimal(int arr[],int n)

{

  int sum=0;

  int count=0;

  for(int i=n-1;i>=0;i--){

    // start from the right side of the array and multiple it with the power of 8

    // starting from 0 and add it to sum

    sum+=pow(8,count)*arr[i];

    count++;

  }

  return sum;

}

int main()

{

  int arr[100],choice;

  string s;

  while(true){

    

    cout<<"******Main Menu******\n1. Convert binary to decimal:\n2. Convert Octal to decimal:\n3. Exit:\n";

    cin>>choice;

    switch(choice){

      case 1:

        cout<<"Enter the binary number : ";

        cin>>s;

        cout<<"Original binary Number: "<<s<<endl;

        // insert each strin character in array

        for(int i=0;i<s.length();i++){

        arr[i] = s[i] - '0';

        }

        cout<<"Its decimal conversion: "<<binToDecimal(arr,s.length())<<endl;

        break;

      case 2:

        cout<<"Enter the octal number : ";

        cin>>s;

        cout<<"Original octal Number: "<<s<<endl;

          // insert each strin character in array

        for(int i=0;i<s.length();i++){

        arr[i] = s[i] - '0';

        }

        cout<<"Its decimal conversion: "<<octToDecimal(arr,s.length())<<endl;

        break;

      case 3:

      // exit program

        exit(0);

      default:

      cout<<"Wrong choice\n";

    }

  }

return 0;

}

OUTPUT:

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