Thread: c++ : binary addition

Doh! Just saw it and assumed it was missed.

i change i=4
no wornings or errors
but the summation is wrong if there is carry

Code:

 #include<iostream>
using namespace std;
int main()
{
	int arr[5],arr1[5],sum[5],carry[6]={0};
int i ,c;

cout<<"number 1.:"<<endl;
for(i=0;i<5;i++)
{
cin>>arr[i];
}
cout<<"number 2.:"<<endl;
for(i=0;i<5;i++)
{
cin>>arr1[i];
}

for(i=0;i<5;i++)
{
    c=arr[i]+arr1[i]+carry[i];
    if(c==0)
   {
        sum[i]=0;
       carry[i+1]=0;
   }
else if(c==1)
{
  sum[i]=1;
  carry[i+1]=0;
}
else if(c==2)
{
 sum[i]=0;
 carry[i+1]=1;
}
else if(c==3)
{
 sum[i]=1;
 carry[i+1]=1;
}
}

for(i=0;i<5;i++)
{
cout<<"sum= "<<sum[i]+carry[i+1];
cout<<endl;
}
return 0;
}

You know that this:

Code:

cout<<"sum= "<<sum[i]+carry[i+1];

is not how carry works.

Courtesy of source code formatter:

Code:

#include<iostream>
using namespace std;
int main()
{
    int arr[5],arr1[5],sum[5],carry[6]= {0};
    int i ,c;

    cout<<"number 1.:"<<endl;
    for(i=0; i<5; i++)
    {
        cin>>arr[i];
    }
    cout<<"number 2.:"<<endl;
    for(i=0; i<5; i++)
    {
        cin>>arr1[i];
    }

    for(i=0; i<5; i++)
    {
        c=arr[i]+arr1[i]+carry[i];
        if(c==0)
        {
            sum[i]=0;
            carry[i+1]=0;
        }
        else if(c==1)
        {
            sum[i]=1;
            carry[i+1]=0;
        }
        else if(c==2)
        {
            sum[i]=0;
            carry[i+1]=1;
        }
        else if(c==3)
        {
            sum[i]=1;
            carry[i+1]=1;
        }
    }

    for(i=0; i<5; i++)
    {
        cout<<"sum= "<<sum[i]+carry[i+1];
        cout<<endl;
    }
    return 0;
}

is not how carry works.

then how ?

Look at ordinary addition:

Code:

 11
 387
+295
----
 682

Would you then write the answer down as 693? No you would not.

i don't know how to write fuction to calculate other than this way

Once you do the carry, you don't do it again. Do you not see how you have already added the carry in the first place?

Code:

 cout<<"sum= "<<sum[i];
        cout<<endl;

you mean like this ?

Right, although at some point you need to remember that you add from right to left.

ok i want the output to be in the same row , like this : 0 0 0 1 0
rather than : 0
0
0
1
0
how can i do it ?

and there is a value i keep getting with the sum -858993460 :S

1. Don't print a new line after every digit.

2. Also make sure your arr1 are reading what you want them to be.