14 replies to this topic

[JP16.1470]

Given two integers A and B, find their exact sum.

This time there are no limitations on A and B (of course, they will fit in memory).

Im stuck on this question and really need to know how to do it.

[ahmed]

what do you mean by exact sum?
if its like normal one just declare three variables two for input and one for answer

[Aereshaa]

Use strings. Store each number in a string, then add them together the way you do it on paper.

[JP16.1470]

aeresnaa would you show an example please!! because i dont know how i could do tht. Thx

[nullbyte]

#include <iostream>
using namespace std;
int main()
{
int a, b;
float c = (a + b);
cin << a;
cout << "\n";
cin << b;
cout << c;
return 0;
}

Is this what you want?

Edited.

Edited by nullbyte, 12 November 2008 - 11:21 PM.

[Aereshaa]

The spec says integers.

[WingedPanther]

We don't do homework for people. The phrase "exact sum" implies something other than the standard result for addition, but it's not clear how.

[Aereshaa]

I think it means bignum.

[JP16.1470]

it does mean bignum.

[dargueta]

Input strings, then convert each digit into a number, then add them right to left, making sure to divide to catch the digit carry.

"12345" + "0492513":
'3'-'0' = 3 (int)
'5'-'0' = 5 (int)
3-5 =  8
'0' + 8 = '8' (char)

EXAMPLE: "9" + "13"
extend to make them the same length --> "09"+"13"
start from right end:
int digitA = '3' - '0'; //cheap conversion trick
int digitB = '9' - '0';
int carry = (digitA + digitB) / 10;  //get overflow
int digitResult = (digitA + digitB) % 10;
char chResult = (char)digitResult + '0';

[Aereshaa]

Write clear code, then optimize.

[dargueta]

Try pseudocode first, then clear code, then optimize. You'll get fewer bugs that way, at least in my experience.