THOUGHTS...: Adding two natural numbers using logical operators & without using arithmetic and unary operators

how to add two numbers without using arithmetic and unary operators

Best Answer was from Sri

#include <stdio.h>
      int add(int a, int b)
      {
     if (!a)
  return b;
     else
  return add((a & b) << 1, a ^ b);
      }

      int main()
      {
     unsigned int a,b;
  printf("Enter the two numbers: \n");

     scanf("%d",&a);
     scanf("%d",&b);
     printf("Sum is: %d",add(a,b));
      }

Regards,

Sri

>>>>>>>>>>>>>>>>>>>>

This looks like is a standard answer for this question - available in INTERNET

>>>>>>>>>>>>>>>>>>>>

KIRAN (sum= s[n]*pow(2,n) + sum;) – this uses + right???

>>>>>>>>>>>>>

#include<stdio.h>

#include<conio.h>

#include<math.h>

void main()

{

int n;

int a[10], b[10], c[10],s[10];

int x ,y ,sum=0;

c[0]= 0;

printf("enter any two numbers below 256 \n"); scanf("%d%d",&x,&y);

for(n=0;n<=9;n++)

{

a[n]= (x>>n)&1;

b[n]= (y>>n)&1;

s[n] = ((a[n])^(b[n]))^c[n];

c[n+1] = (a[n] & b[n])|(b[n] & c[n])|(c[n] & a[n]); }

for(n=9;n>=0;n--)

{

printf("%d\t",s[n]);

sum= s[n]*pow(2,n) + sum;

}

printf("\nsum = %d\n", sum);

}

thanks

kiran k

VIDYASAGAR

>>>>>>>>>>>

#include <stdio.h>

int add(int a, int b);

main()
{
      int a,b;
     printf("Enter the two numbers: \n");

            scanf("%d",&a);
            scanf("%d",&b);
            printf("Sum of given 2 numbers is: %d",add(a,b));

}

int add(int a, int b)
{
            if (!a)
                return b;
            else
   {
    int x = (a & b)<<1;
    int y = a ^ b;
    int z = add(x,y);
    return z;
   }
}

Thanks & Regards,
Vidyasagar

MANOHAR

>>>>>>>>

function prog()

a=40;

b=13;

ta=a;

tb=b;

v=0;

c=0;

clc

for i=1:16

s=bitxor(bitxor(bitand(a,1),bitand(b,1)),bitand(c,1));

v=v+s*(2^(i-1));

c=bitor(bitor(bitand(bitand(a,1),bitand(b,1)),bitand(bitand(a,1),bitand(c,1))),bitand(bitand(b,1),bitand(c,1)));

a=bitshift(a,-1);

b=bitshift(b,-1);

end

disp(v);

>>>>>>>>>>>>>>>>>

ABHINAY

>>>>>>>>>>>>>>>>

a=0;

x=(dec2bin(5))

y=(dec2bin(200))

t='';

if length(x)<8

for i=1:(8-length(x))

t(i)='0';

end

else

t='';

end

x=seqreverse([t x]);

t='';

if length(y)<8

for i=1:(8-length(y))

t(i)='0';

end

else

t='';

end

y=seqreverse([t y]);

for i=1:8

add(i)=bitxor(bitxor(str2num(x(i)),str2num(y(i))),a);

a=bitor(bitor(bitand(str2num(x(i)),str2num(y(i))),bitand(str2num(x(i)),a)),bitand(str2num(y(i)),a));

end

ad=seqreverse(add);

result=bin2dec(strrep(num2str(ad),' ',''))

>>>>>>>>>>>

SWETHA gave me logic but it is not acceptable.

>>>>>>>>>

BHIMSEN JOSHI

>>>>>>>>>>

#include<stdio.h>

void main()

{

int i;

int a = 255,b = 256;

int s=0,c=0,k, ai, bi ;

for(i=0;i<9;i++)

{

ai = ((a>>i)&1);

bi = ((b>>i)&1);

k = ((((ai^bi)^c))<<i);

s = s|k;

c = (ai&c) | (bi&c) | (ai&bi);

}

printf("%d",s);

}

From: bhimsen [mailto:bhimsen@cmcltd.com]
Sent: Thursday, July 17, 2008 11:30 AM
To: 'bhimsen'; 'bhimsen'; 'Manohar'; 'Srikanth P'; 'Abhniay CMC'; 'K_Suresh_CMC'; 'Kattamuri_CMC'; 'Kiran K_CMC'; 'Mani_CMC'; 'Meena_CMC'; 'Murali_CMC'; 'Pavan Kumar G'; 'Pavani Madhira CMC'; 'Rajani G'; 'rrk@cmcltd.com'; 'Sadalakshmi M CMC'; 'Sivakumar'; 'Sravan_B'; 'SravanKumar_GV'; 'sravanthi.batchu@cmcltd.com'; 'Sriraja kumari'; 'Swetha Tattari CMC'; 'Usha_CMC'; 'V.Satish_CMC'; 'Venkat Prasad D'; 'Venkata Krishna R'; 'Vidyasagar_CMC'; 'Vijay_CMC'; 'VLV Naresh Kumar'; 'Santosh Kumar'; 'Venkata Krishna R'; 'V.Satish_CMC'
Subject: RE: C question # 2 - send answers only to me
Importance: High

Is every one busy or cannot solve the simple problem?

None of the team members answered it correctly & completely.

I was thinking it is a 15 mins problem.

I received only one answer from Kiran.

From: bhimsen [mailto:bhimsen@cmcltd.com]
Sent: Wednesday, July 16, 2008 1:06 PM
To: 'bhimsen'; 'Manohar'; 'Srikanth P'; 'Abhniay CMC'; 'K_Suresh_CMC'; 'Kattamuri_CMC'; 'Kiran K_CMC'; 'Mani_CMC'; 'Meena_CMC'; 'Murali_CMC'; 'Pavan Kumar G'; 'Pavani Madhira CMC'; 'Rajani G'; 'rrk@cmcltd.com'; 'Sadalakshmi M CMC'; 'Sivakumar'; 'Sravan_B'; 'SravanKumar_GV'; 'sravanthi.batchu@cmcltd.com'; 'Sriraja kumari'; 'Swetha Tattari CMC'; 'Usha_CMC'; 'V.Satish_CMC'; 'Venkat Prasad D'; 'Venkata Krishna R'; 'Vidyasagar_CMC'; 'Vijay_CMC'; 'VLV Naresh Kumar'; 'Santosh Kumar'; 'Venkata Krishna R'; 'V.Satish_CMC'
Subject: C question # 2 - send answers only to me