C语言 以二进制表示无符号整数

Question

如何将无符号整数表示为二进制？

Answer 1

若要创建某个整数值的字符串表示形式，可以使用以下代码：

#include <stdlib.h>
int main(int argc, char *argv[]) {
  int j;
  unsigned int value = 1024+2048+4096; // some value
  char mask[8*sizeof(unsigned int) + 1] = {0};
  for (j = 0; j < (8*sizeof(unsigned int) + 1); j++) {
    mask[j] = (value << j) & (1 << (8*sizeof(unsigned int)-1)) ? '1' : '0';
  }
  printf("value is b%sn", mask);
  return 0;
}

Answer 2

试试这个：

#include<stdio.h>
int main(void) {
int a,i,k=1;
int arr[32]; \ taken an array of size 32
for(i=0;i <32;i++) 
{
    arr[i] = 0;   \initialised array elements to zero
}
printf("enter a numbern");
scanf("%d",&a);  \get input from the user
for(i = 0;i < 32 ;i++)
{
    if(a&k)    \bit wise and operation
    {
        arr[i]=1;
    }
    else
    {
        arr[i]=0;
    }
    k = k<<1; \left shift by one place evry time
}
for(i = 31 ;i >= 0;i--)
{
    printf("%d",arr[i]);   \print the array in reverse
}
return 0;
}