C Program to Add 2 Binary Strings

// C Program to Add 2 Binary Strings
// and Print their Binary Sum
#include <stdio.h>
#include <string.h>

// Function to add two Binary Strings
void sum(char b1[], char b2[], int l1, int l2)
{
    int carry = 0, temp, num1, num2, i;
    char result[100];

    result[l1 + 1] = '\0';

    // This loop will add Both Strings till
    // second have characters in it.
    while (l2 > 0) {
        num1 = b1[l1 - 1] - '0';
        num2 = b2[l2 - 1] - '0';
        temp = num1 + num2 + carry;
        carry = 0;
        if (temp >= 2) {
            carry = 1;
            temp = temp % 2;
        }
        result[l1] = temp + '0';
        l1--;
        l2--;
    }

    // This loop will add leftover
    // characters of first Strings.
    while (l1 - 1 >= 0) {
        temp = b1[l1 - 1] + carry - '0';
        if (temp >= 2) {
            carry = 1;
            temp = temp % 2;
        }
        result[l1] = temp + '0';
        l1--;
    }

    // Add last carry to result string
    if (carry) {
        result[0] = '1';
    }
    else {
        // if there is no carry then we will shift
        // each character by one place in left side.
        for (i = 0; i < strlen(result) - 1; i++) {
            result[i] = result[i + 1];
        }
        result[strlen(result) - 1] = '\0';
    }

    // printing result
    printf("%s + %s = %s\n", b1, b2, result);
}

// Driver code
int main()
{
    char b1[100] = "1001", b2[100] = "1001";
    int l1, l2;

    printf("Enter binary number 1: ");
    printf("%s \n", b1);
    printf("Enter binary number 2: ");
    printf("%s \n", b2);
    l1 = strlen(b1);
    l2 = strlen(b2);

    // calling function to add strings
    if (l1 > l2) {
        sum(b1, b2, l1, l2);
    }
    else {
        sum(b2, b1, l2, l1);
    }

    return 0;
}

#include <stdio.h>

int main() {

      long binary1=10000, binary2=10000;
    int i = 0, remainder = 0, sum[20];
 
    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;
}

#include <stdio.h>
#include <string.h>

char *addBinary(char *a, char *b) {
    int len1 = strlen(a);
    int len2 = strlen(b);
    int carry = 0, i = len1-1, j = len2-1;
    int maxLen = len1 > len2 ? len1 : len2;
    char *result = (char*)malloc((maxLen + 1) * sizeof(char)); // allocate memory for result string
    result[maxLen] = '\0';

    // add binary digits from right to left
    while (i >= 0 || j >= 0) {
        int sum = carry;
        if (i >= 0) sum += a[i--] - '0';
        if (j >= 0) sum += b[j--] - '0';

        carry = sum >> 1; // carry is 1 if sum is 2 or greater, 0 otherwise
        result[--maxLen] = (sum & 1) + '0'; // set the rightmost bit of result to the sum's least significant bit
    }

    if (carry) { // if there is a final carry, prepend it to the result
        result = (char*)realloc(result, (strlen(result) + 2) * sizeof(char)); // reallocate memory for bigger result string
        memmove(result + 1, result, strlen(result) + 1); // shift result string to the right by 1
        result[0] = '1'; // set the leftmost bit to 1
    }

    return result;
}

int main() {
    char a[] = "101";
    char b[] = "1101";
    char *result = addBinary(a, b);
    printf("Sum of %s and %s is %s\n", a, b, result);
    free(result); // free memory allocated for result string
    return 0;
}

#include <stdio.h>
#include <string.h>

#define MAX_LEN 100

// Function to add two binary strings
char* addBinary(char* a, char* b) {
    static char result[MAX_LEN]; // Resultant binary string
    int len_a = strlen(a);
    int len_b = strlen(b);
    int carry = 0; // Initialize carry to 0
    int i = len_a - 1, j = len_b - 1, k = 0; // Index variables

    // Loop through the binary strings from right to left
    while (i >= 0 || j >= 0 || carry == 1) {
        int sum = carry;
        if (i >= 0) sum += a[i--] - '0'; // Convert character to integer
        if (j >= 0) sum += b[j--] - '0'; // Convert character to integer
        result[k++] = (sum % 2) + '0'; // Convert integer to character
        carry = sum / 2;
    }

    // Reverse the resultant binary string
    int len_result = strlen(result);
    for (int i = 0; i < len_result / 2; i++) {
        char temp = result[i];
        result[i] = result[len_result - i - 1];
        result[len_result - i - 1] = temp;
    }

    return result;
}

int main() {
    char a[MAX_LEN], b[MAX_LEN];
    strcpy(a, "11");
    strcpy(b, "11");
    printf("The sum of %s and %s is %s\n", a, b, addBinary(a, b));
    return 0;
}