Write a program to convert Binary to Decimal

#include<conio.h>
#include<stdio.h>
#include<math.h>
int main()
{
int no,i=0,j,a,r=0;
printf("\nEnter binary number");
scanf("%d",&no);
while(no!=0)
{
a=no%10;
no=no/10;
r=r+a*pow(2,i);
i++;
}
printf("\nDecimal number is:%d",r);
}