decimal_to_binary.c

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

// function for concatenation
char* concat(const char *s1, const char *s2)
{
    char *result = malloc(strlen(s1) + strlen(s2) + 1); // +1 for the null-terminator

    strcpy(result, s1);
    strcat(result, s2);
    return result;
}



// main function
int main()
{
    int inBits, i, c, j, k;

    FILE *fp = fopen("binary.txt", "a");

    char* temp[32];

    // logic here
    for(c = 0; c < 32; c++){
        //printf("%d:" ,c+1);
        char *bin = malloc(5 + 1);

        for(i = 4; i >= 0; i--){
            if((c & (1 << i)) != 0){
                printf("1");
                strcat(bin, "1");

            }else{
                printf("0");
                strcat(bin, "0");
            }
        }

        printf("\n");
        temp[c] = bin;
   }

    printf("\n\nconcatenating ...\n");
    for(k = 0; k < 32; k++){
        // first part of the code
        char* f_p = temp[k];

        for (j = 0; j < 32; j++){
            // second part of the code
            char* s_p = temp[j];

            // concatenating two part
            char* line = concat(f_p, s_p);
            printf("%s\n", line);

            fprintf(fp,"%s\n", line);

        }
    }


    // closing file
    fclose(fp);
    return 0;
}