converting decimal-number to binary-number - c

Question

My program should convert a decimal number into a binary number.
The first for loop is for calculating the binary number.
The second loop puts the msb into the first element of the array.
It is an exercise and the msb has to be in the first element.
I do not understand where the mistake is, help is very much appreciated.
#include<stdio.h>
#include<stdlib.h>
int main(void){
int i;
int bits[16];
int bits_2[16];
int number;
int decimal;
int rest;
int msb;
int result=1;
printf( "Input number smaller than 65536: ");
scanf("%d", &decimal);
if(decimal >= 65536) {
printf( "\n\nincorrect input!");
return EXIT_FAILURE;
}
number=decimal;
for(i=0; result!=0; i++){
result = decimal / 2;
rest = result %2;
bits[i]=rest;
msb = i;
return msb;
}
printf("\n\n %d as binary number : ", number);
for(i=msb; bits[i]>=bits[0]; i--){
bits_2[msb-i] = bits[msb];
printf("%d", bits_2[msb-i]);
}
return 0;
}

Answer 1

result = number = decimal;
for(bits[0]=msb=i=0; result != 0; i++){
bits[i] = result % 2;
result = result / 2;
msb = i;
}
printf("\n\n %d as binary number : ", number);
for(i=msb; i >= 0; i--){
bits_2[msb-i] = bits[i];
printf("%d", bits_2[msb-i]);
}

Answer 2

This is your code with some changes to make it work (you can improve it)
#include<stdio.h>
#include<stdlib.h>
int main(void){
int i;
int bits[16];
int bits_2[16];
int number;
int decimal;
int rest;
int msb;
int result=1;
printf( "Input number smaller than 65536: ");
scanf("%d", &decimal);
if(decimal >= 65536) {
printf( "\n\nincorrect input!");
return EXIT_FAILURE;
}
number=decimal;
for(i=0; result!=0; i++){
result = number / 2; //change this line
rest = number %2; // change this line
number=result; // add this line
bits[i]=rest;
msb = i;
// return msb; //delete this line
}
printf("\n\n %d as binary number : ", decimal); // change this line
for(i=msb; i+1; i--){ // change the condition
// bits_2[msb-i+1] = bits[msb]; // delete this line
printf("%d", bits[i]); // change this line
}
return 0;
}

Answer 3

I noticed that you have a lot of useless variables so this is a compact version of your program:
#include <stdio.h>
#include <stdlib.h>
int main(void){
int i;
int bits[16];
unsigned int decimal;
int rest;
int result=1;
printf( "Input number smaller than 65536: ");
scanf("%d", &decimal);
if(decimal >= 65536) {
printf( "\n\nincorrect input!");
return EXIT_FAILURE;
}
else
printf("\n\n %d as binary number : ", decimal);
for(i=0; result!=0; i++){
result = decimal / 2;
rest = decimal %2;
decimal=result;
bits[i]=rest;
}
i--;
for(; i+1; i--){
printf("%d", bits[i]);
}
return 0;
}