Question

C++ problem

where should I do overflow part? in this code

do not write a new code for me please

///////////////////

// this program read two number from the user

// and display the sum of the number

#include <iostream>

#include <string>

using namespace std;

const int MAX_DIGITS = 10; //10 digits

void input_number(char num[MAX_DIGITS]);

void output_number(char num[MAX_DIGITS]);

void add(char num1[MAX_DIGITS], char num2[MAX_DIGITS], char result[MAX_DIGITS], int &base);

int main()

{

    // declare the array = {'0'}

    char num1[MAX_DIGITS] ={'0'};

    char num2[MAX_DIGITS] ={'0'};

    char result[MAX_DIGITS] ={'0'};

    int base;

    cout << " please enter 10 digits number for this program." << endl << endl;

    // base on 2-35

    cout << " what base for your numbers? (2-35)" << endl<< endl;

    cin >> base;

    cin.ignore(100,'\n');

    cout << " Enter the first number: " << MAX_DIGITS << " digits " << endl << endl;

    // call the input  number function to read the input

    input_number(num1);

    cout << "Enter the second number: "<< MAX_DIGITS << " digits" << endl << endl;

    // call the input  number function to read the input

    input_number(num2);

    // sum of the number

    add(num1,num2,result,base);

    // output

    cout << endl;

    cout << "Sum of ";

    output_number(num1);

    cout << " and ";

    output_number(num2);

    cout << " is ";

    output_number(result);

    cout << endl;

    return 0;

}

//input function

void input_number(char num[MAX_DIGITS])

{

    char ch = '0';

    int n = 0;

    // read the character from user

    while((ch = cin.peek())!=' ' && n < MAX_DIGITS)

    //store character into array

    {

        num[n]= ch;

        n++;

        cin.get(ch);

    }

        cin.ignore(100, '\n');

        //reverse digits in the array to do sum

        for (int i= 0; i <n/2 ; i++)

        {

            char temp = num[i];

            num[i]= num[n-1-i];

            num[n-1-i] = temp;

        }

}

//output function

void output_number(char num[MAX_DIGITS])

{

    for (int i=MAX_DIGITS -1 ; i>=0 ; i--)

    {

    if(num[i]!=0)

    {

    cout <<num[i];

    }

    }

}

// sum function

void add(char num1[MAX_DIGITS], char num2[MAX_DIGITS], char result[MAX_DIGITS], int &base)

{

    int temp_num1, temp_num2,sum;

    int carry1 =0;

    int carry2 =0;

    char temp;

    // repeat the loop for all digits of the array

    for (int i=0; i <MAX_DIGITS ; i++)

    {

        //check if char between 0-9

        if (num1[i]>='0'&& num1[i]<'0'+10) //'0'-'9'

        {

        // change maybe

            temp_num1 = num1[i]-'0';

        }

        else

        {

            //  to uppercase

            temp = toupper(num1[i]);

            // check if between A-Z

            if (temp >= 'A' && temp <='Z')

            {

                temp_num1 = temp-'A'+10;

            }

            else

            {

                cout << " input invaild " << endl;

            }

        }

        // same as num1

        if (num2[i] >= '0' && num2[i] <'0'+10)

        {

            temp_num2 = num2[i] - '0';

        }

        else

        {

            // to uppercase

            temp = toupper(num2[i]);

            // check if between A-Z

            if (temp >= 'A' && temp <= 'Z')

            {

                temp_num2 = temp -'A'+10;

            }

            else

            {

                cout << "input invaild" << endl;

            }

        }

        carry1 = carry2;

        //calculate

        sum = (temp_num1+temp_num2+carry1)% base;

        //carry 2

        carry2 = (temp_num1+temp_num2+carry1)/ base;

        // check sum between 0-10

        if (sum >= 0 && sum < 10)

        {

            result[i] = char('0' + sum);

        }

        // else between 10-35

        else if (sum >=10 && sum <35)

        {

            result[i] = char ('A' +sum -10);

        }

    }

}

Answer 1

You must write overflow part in method add() at this code because it part is overflowing.

//calculate

        sum = (temp_num1+temp_num2+carry1)% base;

        //carry 2

        carry2 = (temp_num1+temp_num2+carry1)/ base;

        // check sum between 0-10

        if (sum >= 0 && sum < 10)

        {

            result[i] = char('0' + sum);

        }

        // else between 10-35

        else if (sum >=10 && sum <35)

        {

            result[i] = char ('A' +sum -10);

        }