String_Containing_Binary.c

#include<stdio.h>

#include<string.h>

#include<math.h>

//function that takes in String and returns an int

int solution(char *S) {

   //we store the length of string S in N

   int N=strlen(S);

   int count=0, number=0,bit=0,j=0;

   //traversing S from the end

   for(int i=N-1;i>=0;i--) {

       //convert S[i] to integer

       bit=S[i]-'0';

       //converting binary to decimal form

       number = number + (pow(2,j) * bit);

       //increasing power of 2 as we move from right to left

       j++;

   }

   //while the number is greater than 0

   while(number>0) {

       //if number is even

       if(number%2==0) {

           //divide it by 2

           number=number/2;

       }

       //if number is odd

       else

           //decrement it by 1

           number = number -1;

       //increment count in every iteration

       count++;

   }

   //returning count

   return count;

}

//main method for testing

int main() {

   //calling above function with a sample string of decimal value 28

   printf("%d",solution("011100"));

}



// OUTPUT
// 7 Process exited after 8.975 seconds with return value 0.
// ...Program finished with exit code 0



/*Explaination 

 Importing the string and math modules to use strlen() and pow()
   count is used to count the number of operation to make the number 0
   Number stores the decimal eqquivalent of given binary
   bit is used to the numerical form of each bit in string
   j is used to increase the power of 2 for binary to decimal conversion

*/

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*/