c programming decimal to binary code example

Example 1: c program from decimal to binary

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

#define D 10

int main()
{
	int i, n, k, vet[D];
   
	printf("FROM DECIMALS TO BINARIES\nEnter decimal: ");
	scanf("%d", &n);
   
	k = 0;
   
	while (n != 0)
	{
		if ((n % 2) == 1) 
			vet[k] = 1;
		else
			vet[k] = 0;
          
		n /= 2;
       
		k++;
	}
	
	printf("Transformed into binary: ");
    
	for(i = k - 1; i >= 0; i --)
		printf("%d", vet[i]);
		
	printf("\n\n");
    
	system("pause");
}

Example 2: how to convert a binary number to decimal in C

#include <math.h>
#include <stdio.h>
int convert(long long n);
int main() {
    long long n;
    printf("Enter a binary number: ");
    scanf("%lld", &n);
    printf("%lld in binary = %d in decimal", n, convert(n));
    return 0;
}

int convert(long long n) {
    int dec = 0, i = 0, rem;
    while (n != 0) {
        rem = n % 10;
        n /= 10;
        dec += rem * pow(2, i);
        ++i;
    }
    return dec;
}