C++ Programming Code Examples
C++ > Algorithms Code Examples
Binary arithmatic
/* Binary arithmatic */
#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<math.h>
void b_to_d(char result[]); //binary to decimal
void d_to_b(int dec,char binary[]); // decimal to binary
main()
{
int ch,n1,n2,i=0,j,k,l,carry,r,x1,x2,x;
char bn1[30],bn2[30],result[30],binary[30];
char multi[30][30];
clrscr();
do
{
printf("<1> input first operand \n");
printf("<2> input second operand \n");
printf("<3> binary addition \n");
printf("<4> binary subtraction \n");
printf("<5> binary multiplation \n");
printf("<6> result to decimal \n");
printf("<7> Exit \n\n");
do
{
printf("enter your choice ");
scanf("%d",&ch);
}while(ch>7 || ch<1);
switch (ch)
{
case 1:
printf("\n input first operand ");
scanf("%d",&n1);
x1=n1;
d_to_b(n1,binary);
for(i=0;binary[i]!='\0';++i)
bn1[i]=binary[i];
bn1[i]='\0';
break;
case 2:
printf("\n input second operand ");
scanf("%d",&n2);
x2=n2;
d_to_b(n2,binary);
for(i=0;binary[i]!='\0';++i)
bn2[i]=binary[i];
bn2[i]='\0';
break;
case 3: //addition
for(i=0;i<30;++i) //reset result
result[i]='\0';
carry=0;
if(strlen(bn1)<strlen(bn2))
r=strlen(bn2);
else
r=strlen(bn1);
for(i=0;i<r;++i)
{
result[i+1]='\0';
if(carry==0)
{
if(bn1[i]-48+bn2[i]-48+carry==1)
result[i]=bn1[i]-48+bn2[i]-48+48;
else
result[i]=0+48;
}
else
{
if(bn1[i]-48+bn2[i]-48+carry==2)
result[i]=0+48;
else
result[i]=1+48;
}
if(bn1[i]-48+bn2[i]-48+carry>1)
carry=1;
else
carry=0;
if(carry==1)
result[i+1]=carry+48;
}
printf("\n%s\n",strrev(result));
break;
case 4: //subtraction
for(i=0;i<30;++i) //reset result
result[i]='\0';
carry=0;
if(strlen(bn1)<strlen(bn2))
r=strlen(bn2);
else
r=strlen(bn1);
for(i=0;i<r;++i)
{
result[i+1]='\0';
if(bn1[i]<bn2[i])
carry=2,--bn1[i+1];
else
carry=0;
if(carry+bn1[i]-48-bn2[i]+48==1)
result[i]=1+48;
else
if(carry+bn1[i]-48-bn2[i]+48==0)
result[i]=0+48;
}
printf("\n%s\n",strrev(result));
break;
case 5: //binary multiplication complited on 27-03-2004
for(i=0;i<30;++i) //reset result
result[i]='\0';
strrev(bn2); // reversing second binary operand
k=0,x=0;
for(i=0;i<strlen(bn2);++i) //creating array for addition
if(bn2[i]=='1')
{
for(j=i+1;bn2[j]!='\0';++j)
multi[k][x++]='0';
for(l=0;bn1[l]!='\0';++j,++l)
multi[k][x++]=bn1[l];
for(;x<30;++j)
multi[k][x++]='0';
++k,x=0;
}
l=0;
for(j=0;j<30;++j) //addition of all columns without carry
{
x=0;
for(i=0;i<k;++i)
x+=(multi[i][j]-48);
multi[0][l++]=x;
}
for(i=0;i<30;++i) //loop for including carry.
if(multi[0][i]>1)
multi[0][i+1]+=((multi[0][i]-(multi[0][i]%2))/2);
printf("\n");
for(i=29;i>=0;--i) // excluding first zero's (0's) of array
if(multi[0][i]!=0)
break;
j=0;
for(;i>=0;--i) // final calculations and print
if(multi[0][i]<48)
{
multi[0][i]%=2;
result[j++]=multi[0][i]+48;
// printf("%d",multi[0][i]);
}
printf("\n");
printf("%s\n",result);
break;
case 6: //result in decimal
b_to_d(result);
printf("\n");
break;
}
n1=x1;
d_to_b(n1,binary);
for(i=0;binary[i]!='\0';++i)
bn1[i]=binary[i];
bn1[i]='\0';
n2=x2;
d_to_b(n2,binary);
for(i=0;binary[i]!='\0';++i)
bn2[i]=binary[i];
bn2[i]='\0';
}while(ch!=7);
printf("\n\n i will wait for your mails");
getch();
return 0;
}
void b_to_d(char result[]) //binary to decimal
{
short int i;
long int dec=0;
strrev(result);
for(i=0;i<strlen(result);++i)
dec+=(result[i]-48)*pow(2,i);
printf("result in decimal is %ld\n",dec);
strrev(result);
}
void d_to_b(int dec,char binary[]) // decimal to binary
{
int i=0;
while(dec>0)
{
binary[i++]=dec%2+48;
binary[i]='\0';
dec-=(dec%2);
dec/=2;
}
}
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