Adding Elements Within An Array

Here is what my program is supposed to do.

Using to premade functions we made previously StringToInt and InputLongInt write two functions: AddLongInts and DisplayLongInt. Write a main program that uses these functions in order to repeatedly input two large integers, add them, and display their sum.

I'm having a couple of problems figuring out what to do.

1. How do I add these individual elements in an array.

all that says is to write two functions:
1. AddLongInts just adds two integers together and returns the result.
2. DisplayLongInt uses cout to display the result returned by the function above.


You should have a main() function in which you create a loop that continusly prompts for the two integers, call AddLongInts to add them together, then call DisplayLongInt() to display the result.

Hi, Rex Overbey

can you be little clear.

already figured it out here it is

/* Author: Rex Overbey
Lab number: CS265 Open Lab 1
Due Date: Friday : 01/30/03
Purpose: Input two large integers, add them, and display their sum.
***********************************************************************************/


#include <iostream>
#include <cstring>
#include <stdlib.h>
#include <iomanip>
#include <cassert>
using namespace std;


const int CAPACITY = 300; //type declarations
typedef int longIntArray[CAPACITY];

void InputLongInt (longIntArray longInt, int & length); //prototypes
int StringToInt (string s);
int AddLongInts (int first, int second);
void DisplayLongInt(longIntArray longInt, int len);

int main()

{

char choice; //choice to continue program

cout << "This program functions in order to repeatedly "
<< "input two large integers, add them, and display their sum.\n\n";

do{

int length=0; //variable declartions for lengths and carry value
int length2=0;
int alength=0;
int car=0;
longIntArray LongInteger,
LongInteger2,
answer;


InputLongInt(LongInteger, length); //first function call


InputLongInt(LongInteger2,length2); //second function call


for (int i=(length-1);i>=0;i--)
{ answer[i+1]=car+AddLongInts(LongInteger[i], LongInteger2[i]);

if(answer[i+1]>=1000)
{
answer[i+1]=answer[i+1]-1000;
car=1;
}
else
{
car=0;
answer[i]=car;
alength=i+1;
}

}

DisplayLongInt(answer, alength);

cout<<"\nDo you want to run the program again:";
cin>>choice;
}
while(choice == 'Y' || choice =='y');

cout <<"\n\nEnd of program";
}


/**********************************************************************************/
// *** Implementation of InputLongInt:

void InputLongInt (longIntArray longInt, int & length)
{
string inString;


cout << "\nEnter a long integer with commas, e.g. 1,218,921: ";
cin >> inString;

int pos;


while (inString != "")
{
length++;
pos = inString.rfind(",", inString.size() - 1);
if (pos == string::npos)
{
longInt[length-1] = StringToInt(inString);
inString = "";
}
else
{
longInt[length-1] = StringToInt(inString.substr(pos+1, 3));
inString.erase(pos, 4);
}
}

}

/* Library of string operations.
*/

/* StringToInt: Receives a string s.
Precondition: s contains only digits, and represents an integer
which is small enough to be stored as an int.
Returns: the integer equivalent of the string s.
***********************************************************************************/



int StringToInt (string s)
{
int result = 0;
int placeValue = 1;
int digit;

for (int i = s.size()-1; i >= 0; i--)
{
assert (isdigit(s[i]));
digit = s[i] - '0';
result += digit * placeValue;
placeValue *= 10;
}

return result;
}



/* AddLongInts: Receives first and second integer.
Precondition: first and second in their raw forms
Post condition: Answer stores total.
***********************************************************************************/
int AddLongInts(int first, int second)
{
int answer;


answer = first + second;

return answer;
}



/*DisplayLongInt: Recieves anwer from AddLongInts()
Precondition: Receives Answer and Len
Postcondition:Outputs to the screen.
***********************************************************************************/

void DisplayLongInt(longIntArray answer, int len)
{
cout << "\nThe answer is: ";
for (int i=(len-1);i>=0;i--)
{

cout << " " << answer[i];
}

cout<<"\n\n";
}