binary_calculator

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#include<iostream>

using namespace std;

void main()

{

int l,a,b=1,decimal=0;

int n;

bool bol=false;

cout<<"Add binary number ";

cin>>n;

while(n>0)

{

a=n%10;

if(a==1||a==0)

{

n=n/10;

a=a*b;

b=b*2;

decimal=decimal+a;

}

else

{

bol=true;

break;

}

}

if(bol==true||n<0)

cout<<"please enter binary number"<<endl;

else

cout<<"Decimal number is "<<decimal<<"."<<endl;

}