#include<stdio.h>
#define MAX 1000

int main(){

   char binaryNumber[MAX],hexaDecimal[MAX];
   int temp;
   long int i=0,j=0;
  
   printf("Enter any number any binary number: ");
   scanf("%s",binaryNumber);

   while(binaryNumber[i]){
      binaryNumber[i] = binaryNumber[i] -48;
      ++i;
   }

   --i;
   while(i-2>=0){
       temp =  binaryNumber[i-3] *8 + binaryNumber[i-2] *4 +  binaryNumber[i-1] *2 + binaryNumber[i] ;
       if(temp > 9)
            hexaDecimal[j++] = temp + 55;
       else
            hexaDecimal[j++] = temp + 48;
       i=i-4;
   }

   if(i ==1)
      hexaDecimal[j] = binaryNumber[i-1] *2 + binaryNumber[i] + 48 ;
   else if(i==0)
      hexaDecimal[j] =  binaryNumber[i] + 48 ;
    else
      --j;

   printf("Equivalent hexadecimal value: ");
   while(j>=0){
      printf("%c",hexaDecimal[j--]);
   }

   return 0;
}
Sample output:
Enter any number any binary number: 1010011011100011110
001001111011110001000100011101110111011110
Equivalent hexadecimal value: 14DC789EF111DDDE

#include<stdio.h>

int main(){

    long int binary1,binary2;
    int i=0,remainder = 0,sum[20];

    printf("Enter any first binary number: ");
    scanf("%ld",&binary1);
    printf("Enter any second binary number: ");
    scanf("%ld",&binary2);

    while(binary1!=0||binary2!=0){
         sum[i++] =  (binary1 %10 + binary2 %10 + remainder ) % 2;
         remainder = (binary1 %10 + binary2 %10 + remainder ) / 2;
         binary1 = binary1/10;
         binary2 = binary2/10;
    }

    if(remainder!=0)
         sum[i++] = remainder;

    --i;
    printf("Sum of two binary numbers: ");
    while(i>=0)
         printf("%d",sum[i--]);

   return 0;
}
Sample output:
Enter any first binary number: 1100011
Enter any second binary number: 1101
Sum of two binary numbers: 1110000

#include<stdio.h>

int binaryAddition(int,int);

int main(){

    long int binary1,binary2,multiply=0;
    int digit,factor=1;

    printf("Enter any first binary number: ");
    scanf("%ld",&binary1);
    printf("Enter any second binary number: ");
    scanf("%ld",&binary2);

    while(binary2!=0){
         digit =  binary2 %10;

         if(digit ==1){
                 binary1=binary1*factor;
                 multiply = binaryAddition(binary1,multiply);
         }
         else
             binary1=binary1*factor;
   
         binary2 = binary2/10;
         factor = 10;
    }

    printf("Product of two binary numbers: %ld",multiply);
   
   return 0;
}

int binaryAddition(int binary1,int binary2){

    int i=0,remainder = 0,sum[20];
    int binarySum=0;

    while(binary1!=0||binary2!=0){
         sum[i++] =  (binary1 %10 + binary2 %10 + remainder ) % 2;
         remainder = (binary1 %10 + binary2 %10 + remainder ) / 2;
         binary1 = binary1/10;
         binary2 = binary2/10;
    }

    if(remainder!=0)
         sum[i++] = remainder;
    --i;
    while(i>=0)
         binarySum = binarySum*10 + sum[i--];

    return binarySum;
}
Sample output:
Enter any first binary number: 1101
Enter any second binary number: 11
Product of two binary numbers: 100111

#include<stdio.h>
#define MAX 1000

int main(){

    long double fraDecimal=0.0,dFractional=0.0 ,fraFactor=0.5;
    long int dIntegral = 0,bIntegral=0,bFractional[MAX];
    long int intFactor=1,remainder,i=0,k=0,flag=0;
    char fraBinary[MAX];

    printf("Enter any fractional binary number: ");
    scanf("%s",&fraBinary);
   
    while(fraBinary[i]){
        
         if(fraBinary[i] == '.')
             flag = 1;
         else if(flag==0)
             bIntegral = bIntegral * 10 + (fraBinary[i] -48);
         else
              bFractional[k++] = fraBinary[i] -48;
         i++;
    }
   
    while(bIntegral!=0){
        remainder=bIntegral%10;
        dIntegral= dIntegral+remainder*intFactor;
        intFactor=intFactor*2;
        bIntegral=bIntegral/10;
    }
   
    for(i=0;i<k;i++){
         dFractional  = dFractional  + bFractional[i] * fraFactor;
         fraFactor = fraFactor / 2;
    }

    fraDecimal = dIntegral + dFractional ;

    printf("Equivalent decimal value: %Lf",fraDecimal);
   
    return 0;
}
Sample output:
Enter any fractional binary number: 11.11
Equivalent decimal value: 3.750000

#include<stdio.h>

int main(){
   
    long double fraDecimal,fraBinary,bFractional = 0.0,dFractional,fraFactor=0.1;
    long int dIntegral,bIntegral=0;
    long int intFactor=1,remainder,temp,i;

    printf("Enter any fractional decimal number: ");
    scanf("%Lf",&fraDecimal);
   
    dIntegral = fraDecimal;
    dFractional =  fraDecimal - dIntegral;

    while(dIntegral!=0){
         remainder=dIntegral%2;
         bIntegral=bIntegral+remainder*intFactor;
         dIntegral=dIntegral/2;
         intFactor=intFactor*10;
    }

   for(i=1;i<=6;i++){
      
       dFractional = dFractional * 2;
       temp =  dFractional;
        
       bFractional = bFractional + fraFactor* temp;
       if(temp ==1)
             dFractional = dFractional - temp;

       fraFactor=fraFactor/10;
   }
  
   fraBinary =  bIntegral +  bFractional;
   printf("Equivalent binary value: %lf",fraBinary);
   
   return 0;
}
Sample output:
Enter any fractional decimal number: 5.7
Equivalent binary value: 101.101100